<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE article
  PUBLIC "-//NLM//DTD JATS (Z39.96) Journal Publishing DTD v1.0 20120330//EN" "http://jats.nlm.nih.gov/publishing/1.0/JATS-journalpublishing1.dtd">
<article article-type="research-article" dtd-version="1.0" specific-use="sps-1.8" xml:lang="pt" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">
	<front>
		<journal-meta>
			<journal-id journal-id-type="publisher-id">cp</journal-id>
			<journal-title-group>
				<journal-title>Ciencias Psicológicas</journal-title>
				<abbrev-journal-title abbrev-type="publisher">Cienc. Psicol.</abbrev-journal-title>
			</journal-title-group>
			<issn pub-type="epub">1688-4221</issn>
			<issn pub-type="ppub">1688-4094</issn>
			<publisher>
				<publisher-name>Facultad de Psicología. Universidad Católica del Uruguay.</publisher-name>
			</publisher>
		</journal-meta>
		<article-meta>
			<article-id pub-id-type="doi">10.22235/cp.v17i2.2630</article-id>
			<article-id pub-id-type="publisher-id">00002</article-id>
			<article-categories>
				<subj-group subj-group-type="heading">
					<subject>Artigos Originais</subject>
				</subj-group>
			</article-categories>
			<title-group>
				<article-title>Qualidade de sono e sonolência diurna em estudantes universitários: testando um modelo explicativo</article-title>
				<trans-title-group xml:lang="en">
					<trans-title>Sleep quality and daytime sleepiness among college students: testing an explanatory model</trans-title>
				</trans-title-group>
				<trans-title-group xml:lang="es">
					<trans-title>Calidad del sueño y somnolencia diurna en estudiantes universitarios: probando un modelo explicativo</trans-title>
				</trans-title-group>
			</title-group>
			<contrib-group>
				<contrib contrib-type="author">
					<contrib-id contrib-id-type="orcid">0000-0002-7126-5036</contrib-id>
					<name>
						<surname>Andrade de Sousa</surname>
						<given-names>Erlândio</given-names>
					</name>
					<xref ref-type="aff" rid="aff1"><sup>1</sup></xref>
				</contrib>
				<contrib contrib-type="author">
					<contrib-id contrib-id-type="orcid">0000-0001-5149-2648</contrib-id>
					<name>
						<surname>Alves Freires</surname>
						<given-names>Leogildo</given-names>
					</name>
					<xref ref-type="aff" rid="aff2"><sup>2</sup></xref>
				</contrib>
				<contrib contrib-type="author">
					<contrib-id contrib-id-type="orcid">0000-0002-0889-6097</contrib-id>
					<name>
						<surname>Lopes Loureto</surname>
						<given-names>Gleidson Diego</given-names>
					</name>
					<xref ref-type="aff" rid="aff3"><sup>3</sup></xref>
				</contrib>
				<contrib contrib-type="author">
					<contrib-id contrib-id-type="orcid">0000-0002-6730-2156</contrib-id>
					<name>
						<surname>Albuquerque da Costa</surname>
						<given-names>Júlio Cezar</given-names>
					</name>
					<xref ref-type="aff" rid="aff4"><sup>4</sup></xref>
				</contrib>
			</contrib-group>
			<aff id="aff1">
				<label>1</label>
				<institution content-type="original"> Universidade Federal de Roraima, Brasil</institution>
				<institution content-type="normalized">Universidade Federal de Roraima</institution>
				<institution content-type="orgname">Universidade Federal de Roraima</institution>
				<country country="BR">Brazil</country>
			</aff>
			<aff id="aff2">
				<label>2</label>
				<institution content-type="original"> Universidade Federal de Alagoas, Brasil, leogildo.alves.freires@gmail.com</institution>
				<institution content-type="normalized">Universidade Federal de Alagoas</institution>
				<institution content-type="orgname">Universidade Federal de Alagoas</institution>
				<country country="BR">Brazil</country>
				<email>leogildo.alves.freires@gmail.com</email>
			</aff>
			<aff id="aff3">
				<label>3</label>
				<institution content-type="original"> Universidade Federal de Roraima, Brasil</institution>
				<institution content-type="normalized">Universidade Federal de Roraima</institution>
				<institution content-type="orgname">Universidade Federal de Roraima</institution>
				<country country="BR">Brazil</country>
			</aff>
			<aff id="aff4">
				<label>4</label>
				<institution content-type="original"> Universidade Federal de Alagoas, Brasil</institution>
				<institution content-type="normalized">Universidade Federal de Alagoas</institution>
				<institution content-type="orgname">Universidade Federal de Alagoas</institution>
				<country country="BR">Brazil</country>
			</aff>
			<!--<pub-date date-type="pub" publication-format="electronic">
				<day>01</day>
				<month>12</month>
				<year>2023</year>
			</pub-date>
			<pub-date date-type="collection" publication-format="electronic">-->
			<pub-date pub-type="epub-ppub">
				<year>2023</year>
			</pub-date>
			<volume>17</volume>
			<issue>2</issue>
			<fpage>1</fpage>
			<lpage>16</lpage>
			<history>
				<date date-type="received">
					<day>13</day>
					<month>07</month>
					<year>2021</year>
				</date>
				<date date-type="accepted">
					<day>24</day>
					<month>07</month>
					<year>2023</year>
				</date>
			</history>
			<permissions>
				<license license-type="open-access" xlink:href="https://creativecommons.org/licenses/by/4.0/" xml:lang="pt">
					<license-p>Este é um artigo publicado em acesso aberto sob uma licença Creative Commons</license-p>
				</license>
			</permissions>
			<abstract>
				<title>Resumo</title>
				<p>O presente estudo teve como objetivo testar, através de equações estruturais, um modelo explicativo da qualidade do sono e da sonolência diurna entre estudantes universitários brasileiros (<italic>N</italic> = 407). Os participantes responderam ao Índice da Qualidade do Sono de Pittsburgh (PSQI), à Escala de Sonolência de Epworth (ESS-BR), ao Questionário de Saúde Geral (QSG-12), à Escala de Avaliação de Fadiga (EAF), à Escala de Estresse Acadêmico (EEA), ao Questionário sobre Tempo de Uso de Drogas (QTUDR) e às informações demográficas. As análises de correlações bivariadas e regressões múltiplas forneceram elementos para a elaboração de um modelo explicativo que incluíram como variáveis explicativas o desconforto psicológico, o estresse acadêmico e o uso de cafeína, como preditores da qualidade do sono e, esta última juntamente com a fadiga, explicando a sonolência diurna. Este modelo apresentou índices adequados de ajuste aos dados empíricos. É possível concluir que maiores níveis de estresse acadêmico, desconforto psicológico, fadiga e uso de cafeína estão associados a menores índices de qualidade do sono entre estudantes universitários. Os resultados demonstram a relevância de considerar variáveis individuais e contextuais para compreender o ciclo vigília-sono no âmbito acadêmico. Essas variáveis devem ser consideradas em futuros estudos que procurem aplicar e avaliar possíveis programas de intervenção.</p>
			</abstract>
			<trans-abstract xml:lang="en">
				<title>Abstract</title>
				<p>The current study aimed to test, through structural equation modeling, an explanatory model of the sleep quality and excessive daytime sleepiness among Brazilian college students (<italic>N</italic> = 407). They answered the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), 12-item General Health Questionnaire, Fatigue Assessment Scale (FAS), Academic Stress Scale (ASS), Drug Use Time Questionnaire (DUTQ), and demographic information. The bivariate correlations and multiple regressions provided subsidies for the building of an explanatory model that included psychological discomfort, academic stress and the use of caffeine as explanatory variables for predicting sleep quality, and in turn the latter together with fatigue explaining daytime sleepiness. This model showed acceptable fit. The study concludes that higher levels of academic stress, psychological distress, fatigue and caffeine use are associated with lower sleep quality rates among university students. These findings shed light on the importance of considering both individual and contextual variables to understand the sleep-wake cycle in an academic context. These variables should be considered in further studies that aim to apply and evaluate possible future intervention actions.</p>
			</trans-abstract>
			<trans-abstract xml:lang="es">
				<title>Resumen</title>
				<p>Este estudio tuvo como objetivo evaluar, vía modelaje por ecuaciones estructurales, un modelo explicativo de la calidad del sueño y somnolencia diurna excesiva en estudiantes universitarios brasileños (N = 407). Los participantes respondieron al Índice de la Calidad del Sueño de Pittsburgh (PSQI), a la Escala de Somnolencia de Epworth (ESS-BR), Cuestionarios de Salud General (QSG-12), la Escala de Evaluación de Fatiga (EAF), la Escala de Estrés Académico (EEA), el Cuestionario sobre el Tiempo de Uso de Drogas (QTUDR) e informaciones demográficas. Los análisis de correlaciones y regresiones ofrecieron respaldo para la elaboración de un modelo explicativo que incluye como variables explicativas el malestar psicológico, el estrés académico y el uso de cafeína como predictores de la calidad de sueño y esta última juntamente con la fatiga, lo que explica la somnolencia diurna. Este modelo presentó índices adecuados de ajuste a los datos empíricos. Se puede concluir que niveles mayores de estrés académico, malestar psicológico, fatiga y uso de cafeína de asocian a índices menores de calidad del sueño entre estudiantes universitarios. Tales resultados ponen en evidencia la importancia de considerar tanto variables individuales cuanto contextuales para entender el ciclo vigilia-sueño en el ámbito académico. Estas variables deben ser consideradas en estudios posteriores que busquen aplicar y evaluar posibles acciones futuras de intervención.</p>
			</trans-abstract>
			<kwd-group xml:lang="pt">
				<title>Palavras-chave:</title>
				<kwd>Qualidade de sono</kwd>
				<kwd>sonolência diurna</kwd>
				<kwd>estresse acadêmico</kwd>
				<kwd>estudantes universitários</kwd>
			</kwd-group>
			<kwd-group xml:lang="en">
				<title>Keywords:</title>
				<kwd>Sleep quality</kwd>
				<kwd>daytime sleepiness</kwd>
				<kwd>academic stress</kwd>
				<kwd>undergraduate students</kwd>
			</kwd-group>
			<kwd-group xml:lang="es">
				<title>Palabras clave:</title>
				<kwd>Calidad del sueño</kwd>
				<kwd>somnolencia diurna</kwd>
				<kwd>estrés académico</kwd>
				<kwd>estudiantes universitarios</kwd>
			</kwd-group>
			<counts>
				<fig-count count="1"/>
				<table-count count="2"/>
				<equation-count count="0"/>
				<ref-count count="81"/>
				<page-count count="16"/>
			</counts>
		</article-meta>
	</front>
	<body>
		<p>O sono é um comportamento ativo, repetitivo e reversível que pode ser usado para diversas finalidades, como processos restaurativos, fisiológicos e cognitivos (<xref ref-type="bibr" rid="B1">Ackermann &amp; Rasch, 2014</xref>; <xref ref-type="bibr" rid="B40">Landmann et al., 2014</xref>; <xref ref-type="bibr" rid="B62">Rasch &amp; Born, 2015</xref>). Dessa forma, dentre outros processos, o sono se torna indispensável para a neurogênese, plasticidade sináptica, atenção, vigília, aprendizagem e consolidação de memórias (<xref ref-type="bibr" rid="B58">Panjwani et al., 2019</xref>).</p>
		<p>No entanto, a sociedade contemporânea apresenta uma crescente demandas por trabalho, estudo e compromissos sociais em horários irregulares, o que acaba por negligenciar mecanismos naturais relacionados ao sono, o que resulta em danos à saúde física e mental das pessoas (<xref ref-type="bibr" rid="B7">Amaro &amp; Dumith, 2018</xref>). Para lidar com os diversos interesses do dia a dia, muitas pessoas preferem sacrificar um tempo de sono, tendo em mente que isso não trará consequências adversas ou danosas (<xref ref-type="bibr" rid="B19">Curcio et al., 2006</xref>).</p>
		<p>Os estudantes universitários são um exemplo disso (<xref ref-type="bibr" rid="B4">Almojali et al., 2017</xref>). Geralmente, apresentam um padrão de sono irregular, caracterizado por alterações na duração, no horário de início e término do sono, ocorrendo mais tarde aos fins de semana em comparação aos horários da semana, provavelmente às demandas sociais, acadêmicas, adaptação ao contexto universitário, falta de supervisão dos pais (<xref ref-type="bibr" rid="B6">Amaral, 2018</xref>; <xref ref-type="bibr" rid="B9">Araújo et al., 2013</xref>; <xref ref-type="bibr" rid="B60">Phillips et al., 2017</xref>). Para se ter uma ideia da gravidade deste fenômeno, tal padrão resulta em alta variação nos hábitos de sono, gerando um débito de sono acentuado, o que não é observado com frequência em populações não clínicas ou que não trabalham em turnos (<xref ref-type="bibr" rid="B42">Lemma et al., 2012</xref>; <xref ref-type="bibr" rid="B43">Li et al., 2017</xref>).</p>
		<p>A qualidade do sono (QS) e a sonolência diurna (SD) têm sido apontadas como fatores que têm uma grande influência na aprendizagem do estudante universitário (<xref ref-type="bibr" rid="B35">Huang et al., 2014</xref>). A avaliação da QS com instrumentos de autorrelato, geralmente, tem uma faceta objetiva (e.g., número de despertares noturnos, latência e duração de sono), mas também uma perspectiva subjetiva (e.g., percepção de profundidade de sono e do nível de restauração que o indivíduo sente ao acordar, além de satisfação geral com o sono; <xref ref-type="bibr" rid="B10">Bertolazi, 2008</xref>). A sonolência é, geralmente, um aumento da propensão a cochilar/adormecer durante o dia ou à incapacidade de manter-se alerta nesse período (<xref ref-type="bibr" rid="B72">Thorpy &amp; Billiard, 2011</xref>). É, geralmente, acompanhada de uma baixa latência de sono, saltos em estágios importantes do sono devido ao débito acumulado, o que é um indicador comum da existência de distúrbios do sono (<xref ref-type="bibr" rid="B38">Kaur &amp; Singh, 2017</xref>).</p>
		<p>Dessa forma, acredita-se que o estudo das condições que interferem nessas variáveis seja uma demanda relevante de investigação e intervenção por parte da comunidade acadêmica, pois, ao se relacionar com aspectos de saúde física e mental, e aspectos cognitivos de aprendizagem e memória, o sono, a qualidade do sono e a sonolência podem interferir no rendimento acadêmico do estudante universitário (<xref ref-type="bibr" rid="B18">Christodoulou et al., 2023</xref>; <xref ref-type="bibr" rid="B22">Fonseca &amp; Genzel, 2020</xref>). Em termos gerais, estudos anteriores já demonstraram algumas variáveis que podem predizer a QS e a SD em uma população universitária, tendo destaque o estresse acadêmico (<xref ref-type="bibr" rid="B5">Alotaibi et al., 2020</xref>), o desconforto psicológico (<xref ref-type="bibr" rid="B56">Najafi Kalyani et al., 2017</xref>), a fadiga (<xref ref-type="bibr" rid="B65">Sajadi et al., 2014</xref>), assim como o uso/abuso de substâncias psicoativas (<xref ref-type="bibr" rid="B81">Zhabenko et al., 2016</xref>).</p>
		<p>No que diz respeito ao fenômeno do estresse, este é definido como um estado de ativação do organismo em resposta à percepção de uma ameaça, real ou imaginada, que é capaz de alterar a sua condição de bem-estar subjetivo, ocasionando sensações de desconforto e/ou desconforto temporários ou permanentes (<xref ref-type="bibr" rid="B41">Lazarus &amp; Folkman, 1984</xref>). Dessa forma, o estresse acadêmico (EA) é definido como uma reação de ativação fisiológica, emocional, cognitiva e comportamental em resposta a estímulos acadêmicos (<xref ref-type="bibr" rid="B26">García &amp; Zea, 2011</xref>). Dentre as principais situações que que os estudantes podem interpretar como estressantes estão: a realização das provas, a apresentação de trabalhos em sala de aula, a sobrecarga de atividades etc. (<xref ref-type="bibr" rid="B27">García-Ros et al., 2012</xref>; <xref ref-type="bibr" rid="B45">Lund et al., 2010</xref>). Estudos anteriores já demonstram os efeitos negativos do EA na QS de universitários em diferentes contextos (<xref ref-type="bibr" rid="B42">Lemma et al., 2012</xref>; <xref ref-type="bibr" rid="B45">Lund et al., 2010</xref>).</p>
		<p>O construto de desconforto psicológico (DP) é entendido como aquele conjunto de transtornos psiquiátricos não severos, não psicóticos, que, geralmente, indicam a presença de ansiedade, depressão, abuso de substâncias e baixa autoeficácia (<xref ref-type="bibr" rid="B49">Massud et al., 2007</xref>), e tem influência na QS. <xref ref-type="bibr" rid="B37">Kaneita et al. (2009</xref>) conduziram um estudo longitudinal prospectivo com adolescentes japoneses e constataram que a perturbação do sono aumenta o risco de desenvolvimento de estado de saúde mental deficitário, e vice-versa. Outros estudos demonstraram que alterações no estado de saúde mental estão intimamente relacionadas às diferenças no estado de sono (<xref ref-type="bibr" rid="B17">Cheng et al., 2012</xref>; <xref ref-type="bibr" rid="B71">Suzuki et al., 2011</xref>).</p>
		<p>A variável da fadiga é, geralmente, entendida como uma sensação de tensão, cansaço ou falta de energia (<xref ref-type="bibr" rid="B25">Fujii et al., 2015</xref>). Estudos recentes indicam que a fadiga pode ser um quadro causado por um estilo de vida considerado não saudável (i.e., comportamentos sedentários; <xref ref-type="bibr" rid="B76">Wang et al., 2019</xref>), sendo um problema prevalente na população adulta (<xref ref-type="bibr" rid="B39">Koohsari et al., 2021</xref>), na qual se incluem os estudantes universitários. Assim, tal variável, de forma similar, tem implicações para a qualidade do sono em diferentes populações (<xref ref-type="bibr" rid="B77">Wylie et al., 2022</xref>). Na relação entre a fadiga normal (em população não clínica) e o sono, tem sido demonstrado que a fadiga está relacionada à baixa qualidade do sono e curta duração do sono, bem como a altos níveis de estresse, além de uma forte relação com a percepção de menores níveis de saúde subjetiva e sonolência (<xref ref-type="bibr" rid="B2">Åkerstedt et al., 2014</xref>). Outro estudo refere-se à alta prevalência de fadiga entre pessoas com distúrbios do sono, tais como insônia, apneia obstrutiva do sono, narcolepsia, etc. (<xref ref-type="bibr" rid="B74">Tsai &amp; Lee-Chiong, 2013</xref>). </p>
		<p>Em suma, é mencionado o uso/abuso de substâncias, uma vez que implica em consequências fisiológicas e cognitivas individuais que, por sua vez, interagem com o ciclo vigília-sono (<xref ref-type="bibr" rid="B46">Madras &amp; Kuhar, 2013</xref>). De acordo com <xref ref-type="bibr" rid="B29">Gillin et al. (2005</xref>), a cafeína tem sido estudada com menos frequência. Em uma metanálise, <xref ref-type="bibr" rid="B28">Gardiner et al. (2023</xref>), constataram prejuízos significativos na eficiência, latência e duração total do sono devido ao uso de cafeína. Há também evidências de que o do uso de cafeína interfere negativamente na QS de acadêmicos (<xref ref-type="bibr" rid="B34">Henriques, 2008</xref>). Além disso, <xref ref-type="bibr" rid="B69">Sin et al. (2009</xref>), em uma revisão sistemática, demostraram que a abstinência de cafeína promove um aumento na QS.</p>
		<p>Diante do panorama apresentado, este estudo teve como objetivo desenvolver um modelo explicativo, através da Modelagem por Equações Estruturais (MEE), da QS e da SD de estudantes universitários brasileiros, tendo como variáveis independentes o DP, o EA, a fadiga e o uso de substâncias psicoativas, considerando a QS e a SD como variáveis critério do modelo. A proposta de um modelo preditivo é uma forma de se obter dados para serem considerados em futuras ações interventivas em relação à saúde e ao rendimento acadêmico dos universitários, que, por sua vez, concorram para a satisfação do estudante em relação à vivência universitária (<xref ref-type="bibr" rid="B44">Lopes et al., 2013</xref>).</p>
		<sec sec-type="materials">
			<title>Materiais e Método</title>
			<sec>
				<title>Participantes</title>
				<p>Participaram 407 estudantes universitários de uma instituição pública de Ensino Superior situada na região Norte do Brasil, localizada na cidade de Boa Vista, Estado de Roraima. Os participantes apresentaram idades que variaram de 18 a 63 anos (<italic>M</italic>= 23 anos; <italic>DP</italic>= 6,75), sendo a maioria do sexo feminino (64,4%), solteiro (82,1%), frequentando cursos diurnos (56%) e cursando psicologia (26,5%). Em relação ao uso/abuso de substâncias: 80,5% dos estudantes usaram cafeína e 51,6% do álcool. Além disso, outras sustâncias foram usadas: tabaco (7,8%), anfetaminas (2,5%), tranquilizantes (1,7%), maconha (7,1%), cocaína (1%), inalantes (0,2%).</p>
			</sec>
			<sec>
				<title>Instrumentos</title>
				<p>Os participantes responderam a um questionário online que, incluía de perguntas sobre a idade, sexo, orientação sexual, estado civil, religião, turno do curso de graduação, uso de substâncias, etc. </p>
				<p><italic>Pittsburg Sleep Scale Index</italic> (PSQI; <xref ref-type="bibr" rid="B15">Buysse et al., 1989</xref>) tem como objetivo avaliar a qualidade do sono no último mês. A versão do PSQI adaptada para o contexto brasileiro (<xref ref-type="bibr" rid="B10">Bertolazi, 2008</xref>) é composta por 19 questões, divididas em sete componentes: a qualidade subjetiva do sono, a latência do sono, a duração do sono, a eficiência habitual do sono, os distúrbios do sono, o uso de medicação para dormir, e a sonolência diurna e distúrbios durante o dia. Para cada componente da medida, o escore pode variar de 0 (<italic>nenhuma dificuldade</italic>) a 3 (<italic>dificuldade grave</italic>), gerando um escore de no máximo 21 pontos. No presente estudo, a escala de resposta foi invertida, de modo que quanto maior a pontuação na PSQI, melhor é a qualidade de sono dos participantes. Neste estudo, segundo <xref ref-type="bibr" rid="B48">Marôco e Garcia-Marques (2006</xref>) o alpha de Cronbach desta medida apresentou fidedignidade moderada (α = 0,82).</p>
				<p><italic>A Escala de Sonolência de Epworth</italic> (ESS; <xref ref-type="bibr" rid="B36">Johns, 1991</xref>) a versão adaptada para o contexto brasileiro (<xref ref-type="bibr" rid="B11">Bertolazi et al., 2009</xref>). Os participantes foram instruídos a indicar suas chances de adormecer em oito situações que envolvem atividades diárias (e.g., “Sentado e lendo”, “Assistindo TV” etc.). Os itens da escala (i.e., oito itens) foram respondidos em uma escala de quatro pontos (variando de 0 = <italic>nunca cochilar</italic> a 4 = <italic>grande probabilidade de cochilar</italic>), apresentando, neste estudo, índice de fidedignidade moderada α = 0,83 (<xref ref-type="bibr" rid="B48">Marôco &amp; Garcia-Marques, 2006</xref>).</p>
				<p><italic>Questionário de Saúde Geral</italic> (QSG-12; <xref ref-type="bibr" rid="B30">Goldberg, 1972</xref>), tem o objetivo de avaliar a saúde mental de pessoas através de questões que versem sobre sintomas psiquiátricos não psicóticos (e.g., “Suas preocupações lhe têm feito perder muito sono?”). Os participantes foram solicitados a responder a uma escala de quatro pontos tipo Likert: para os itens negativos, as alternativas de resposta variam de 1 = <italic>absolutamente não</italic>, a 4 =<italic>muito mais que de costume</italic>; para os itens positivos, a escala de resposta varia de 1 =<italic>mais que de costume</italic>, a 4 = <italic>muito menos que de costume</italic>. Após a inversão dos itens negativos, gerou-se uma pontuação total do QSG-12, de forma que maiores pontuações indicavam maior desconforto psicológico. No presente estudo, o índice de fidedignidade do QSG-12 foi moderado α = 0,80 (<xref ref-type="bibr" rid="B48">Marôco &amp; Garcia-Marques, 2006</xref>).</p>
				<p><italic>Escala de Avaliação de Fadiga</italic> (EAF; <xref ref-type="bibr" rid="B52">Michielsen et. al, 2004</xref>), é composta por 10 itens, tais como (e.g., “Sinto-me incomodado devido à fadiga”; “Fico cansado muito rapidamente” etc.). Tais itens foram respondidos em escala Likert de cinco pontos (variando de 1 = <italic>nunca</italic>, a 5 = <italic>sempre</italic>), conforme o participante tem se sentido nos últimos dias em relação à fadiga. O índice de fidedignidade da EAF, neste estudo, foi moderado α = 0,87 (<xref ref-type="bibr" rid="B48">Marôco &amp; Garcia-Marques, 2006</xref>).</p>
				<p><italic>Escala de Estresse Acadêmico</italic> (EEA). Consiste em versão adaptada da Escala de Estresse no Trabalho (EET; <xref ref-type="bibr" rid="B59">Paschoal &amp; Tamayo, 2004</xref>). Esta foi adaptada para o contexto universitário (<xref ref-type="bibr" rid="B24">Freires et al., 2018</xref>). Seus 12 itens (e.g., “A forma como as tarefas são distribuídas entre as disciplinas tem me deixado nervoso”.) foram respondidos em uma escala tipo Likert de cinco pontos (variando de 1 = <italic>discordo totalmente</italic>, a 5 <italic>= concordo totalmente</italic>). No presente estudo, a consistência interna da EEA foi adequada (α = 0,88).</p>
				<p><italic>Questionário sobre Tempo de Uso de Drogas</italic> (QTUDR). Tal instrumento, composto por 27 itens, foi empregado para avaliar a frequência do uso de inúmeras substâncias por parte da amostra: tabaco, anfetaminas e estimulantes, tranquilizantes, álcool, maconha, cocaína ou crack e inalantes. Dessa forma, o QTUDR possibilitou a identificação de consumidores ocasionais e dependentes de algumas das drogas mais comuns (<xref ref-type="bibr" rid="B47">Mariño et al., 1998</xref>).</p>
			</sec>
			<sec>
				<title>Procedimento</title>
				<p>A coleta dos dados foi realizada online. Os sujeitos foram contatados previamente, via e-mail e redes sociais, estando os instrumentos supracitados dispostos por meio da ferramenta Lime Survey<italic>.</italic> Todos os instrumentos eram autoaplicáveis, contendo as instruções necessárias para proceder às respostas; ademais, os pesquisadores envolvidos se colocaram à disposição em endereço eletrônico para esclarecer eventuais dúvidas quanto à participação no estudo. Foram seguidas todas as prerrogativas dispostas na Resolução nº 510/2016, do Conselho Nacional de Saúde, no que tange à regulamentação das pesquisas com seres humanos. Esta pesquisa foi aprovada pelo Comitê de Ética em Pesquisa de uma instituição pública do norte brasileiro (parecer nº 726.580). </p>
			</sec>
			<sec>
				<title>Análise dos dados</title>
				<p>Para a análise de dados, utilizou-se o software R (<xref ref-type="bibr" rid="B61">R Development Core Team, 2015</xref>). As estatísticas descritivas, para fins de caracterização amostral, assim como as análises de correlação e regressão linear (i.e., relações entre as variáveis antecedentes com as variáveis critério: QS e SD) foram realizadas pela interface Rcommander do pacote Rcmdr (<xref ref-type="bibr" rid="B23">Fox, 2017</xref>).</p>
				<p>Para a testagem do modelo teórico explicativo, utilizou-se o pacote lavaan (<xref ref-type="bibr" rid="B64">Rosseel, 2012</xref>), aplicando-se o método de estimação Robust Maximum Likelihood (MLR). Para fins de avaliação do ajuste do modelo, os seguintes indicadores de ajuste dos dados foram adotados: (a) razão qui-quadrado por graus de liberdade (χ²/<italic>gl</italic>), aceitando-se valores entre 2 e 3, admitindo-se até 5; (b) Comparative Fit Index (CFI) e Tucker-Lewis Index (TLI), aceitando-se valores iguais ou superiores a 0,90, (c) Standardized Root Mean Square Residual (SRMR), admitindo-se como recomendável um valor abaixo de 0,08, e Root Mean Square Error Approximation (RMSEA), cujos valores recomendados se situam entre 0,05 e 0,08, admitindo-se até 0,10, em que os intervalos de confiança (90%) não incluam um valor maior que 0,10 (<xref ref-type="bibr" rid="B66">Schreiber et al., 2006</xref>). Quanto aos testes inferenciais para os efeitos indiretos no modelo explicativo, utilizou-se o procedimento de Bootstrap Confidence Intervals com 10,000 reamostragens (<xref ref-type="bibr" rid="B33">Hayes, 2017</xref>), em que os efeitos são considerados significativos quando o intervalo de confiança não inclui o zero.</p>
			</sec>
		</sec>
		<sec sec-type="results">
			<title>Resultados</title>
			<sec>
				<title>Correlatos da qualidade do sono e sonolência diurna de estudantes universitários</title>
				<p>Com a finalidade de conhecer em que medida as variáveis independentes do presente se estudo se correlacionam com as variáveis critério, QS e SD, realizaram-se correlações entre as mesmas. Quanto às questões sobre a frequência de uso de substâncias, apenas o uso de cafeína e álcool foram relatados em maior medida pela amostra, portanto, as variáveis com as demais substâncias foram desconsideradas das análises. Em relação aos resultados, conforme é possível observar na <xref ref-type="table" rid="t1">Tabela 1</xref>, a SD se relacionou negativamente com a QS. Ademais, a SD apresentou relações significativas e positivas com o DP, EA, fadiga, sendo a relação negativa com o uso de cafeína; não houve relação significativa com o uso de álcool. Frente à QS, esta se associou negativa e significativamente com todas as variáveis (i.e., DP, EA, fadiga e uso de cafeína) sendo o uso de álcool, a única exceção. </p>
				<p>
					<table-wrap id="t1">
						<label>Tabela 1:</label>
						<caption>
							<title>Correlatos da qualidade do sono e sonolência diurna de estudantes universitarios</title>
						</caption>
						<graphic xlink:href="1688-4221-cp-17-02-e2630-gt1.jpg"/>
						<table-wrap-foot>
							<fn id="TFN1">
								<p>* <italic>p</italic> &lt; 0,05 ** <italic>p</italic> &lt; 0,01</p>
							</fn>
						</table-wrap-foot>
					</table-wrap>
				</p>
			</sec>
			<sec>
				<title>Preditores da qualidade de sono e sonolência diurna de estudantes universitários</title>
				<p>Por não se identificar estudos prévios que permitam consolidar uma elaboração teórica a respeito, decidiu-se realizar uma regressão linear múltipla por etapas (<italic>stepwise</italic>), procurando evitar o efeito de multicolinearidade, visando definir os preditores significativos da QS e SD de estudantes universitários. As variáveis antecedentes foram selecionadas, para ambas os variáveis critérios, a partir da significância de seus respectivos coeficientes de correlação, assim como pela direcionalidade teórica entre as mesmas. Os resultados desta análise são apresentados na <xref ref-type="table" rid="t2">Tabela 2</xref>.</p>
				<p>
					<table-wrap id="t2">
						<label>Tabela 2:</label>
						<caption>
							<title>Regressão linear múltipla da qualidade de sono e sonolência diurna de estudantes universitarios</title>
						</caption>
						<graphic xlink:href="1688-4221-cp-17-02-e2630-gt2.jpg"/>
						<table-wrap-foot>
							<fn id="TFN2">
								<label>Nota:</label>
								<p> B: coeficiente de regressão não padronizado; β: coeficiente de regressão padronizado; t: Estatística t; <italic>p</italic>: valor-p.</p>
							</fn>
						</table-wrap-foot>
					</table-wrap>
				</p>
				<p>Para a QS (<xref ref-type="table" rid="t2">Tabela 2</xref>), as variáveis DP, EA e o uso de cafeína entraram como preditores significativos, todas apresentando coeficientes negativos. Especificamente, em conjunto, tais variáveis (<italic>R</italic> = 0,55, <italic>F</italic>(3, 404) = 56,94, <italic>p</italic> &lt; 0,001) explicaram 31,2% da variância total (R<sup>2</sup> ajustado). Para o segundo modelo de regressão, para explicar a SD, observou-se (<xref ref-type="table" rid="t2">Tabela 2</xref>) que a fadiga, positivamente, e a QS, negativamente, predisseram de forma significativa tal variável critério. Conjuntamente, tal modelo (<italic>R</italic> = 0,43, <italic>F</italic>(2, 406) = 47,25, <italic>p</italic> &lt; 0,001) explicou 19,1% da variância total (R<sup>2</sup> ajustado).</p>
			</sec>
			<sec>
				<title>Elaboração do modelo explicativo: qualidade de sono de estudantes universitários</title>
				<p>Os resultados acima descritos sugerem que, entre estudantes universitários, a QS e a SD podem ser compreendidas por meio dos níveis de EA, DP, fadiga e uso de cafeína, isto tendo em vista o poder preditivo dessas variáveis. Deste modo, a partir destes resultados é possível pensar em uma sequência (i.e., modelo explicativo) que reúne o DP, o EA e o uso de cafeína como preditores da QS, e esta última juntamente com a fadiga, por sua vez, explicando a SD. Tal cenário analítico correspondeu à elaboração de um modelo explicativo, testado a partir da MEE, apresentado na <xref ref-type="fig" rid="f1">Figura 1</xref>.</p>
				<p>
					<fig id="f1">
						<label>Figura 1:</label>
						<caption>
							<title>Modelo explicativo da qualidade de sono de estudantes universitarios</title>
						</caption>
						<graphic xlink:href="1688-4221-cp-17-02-e2630-gf1.jpg"/>
					</fig>
				</p>
				<p>Os índices de ajuste do modelo (<xref ref-type="fig" rid="f1">Figura 1</xref>) foram adequados: χ²/gl = 1,14, CFI = 0,96, TLI = 0,91, SRMR = 0,030 e RMSEA = 0,073 (0,031 - 0,080). De igual modo, os efeitos indiretos foram testados. Especificamente, o DP (β = 0,09, IC95% = 0,030/0,082), o EA (β = 0,03, IC95% = 0,003/0,027) e o uso de cafeína (β = -0,03, IC95% = -0,498/-0,030) predisseram a SD, através da QS. Finalmente, determinou-se a variância explicada do modelo (<xref ref-type="bibr" rid="B68">Shrout &amp; Bolger, 2002</xref>), observando-se que o modelo foi capaz de explicar 47% da variância da QS e SD dos estudantes universitários.</p>
			</sec>
		</sec>
		<sec sec-type="discussion">
			<title>Discussão</title>
			<p>Até recentemente os estudos empíricos acerca do padrão de sono e SD entre estudantes universitários enfatizavam tão somente a verificação dos níveis de mensuração de tais variáveis, dando menor atenção aos potenciais preditores desses fenômenos (<xref ref-type="bibr" rid="B35">Huang et al., 2014</xref>; <xref ref-type="bibr" rid="B75">Wang &amp; Bíró, 2021</xref>). Dessa forma, o presente estudo objetivou testar um modelo explicativo da QS e da SD de uma amostra de universitários brasileiros via um modelo estrutural. Os resultados indicaram que o DP, o EA e o uso de cafeína impactaram negativamente a QS. Em seguida, a QS (negativamente) e a fadiga (positivamente) explicaram os níveis de SD da amostra. O ajuste dos dados ao modelo proposto foi adequado (<xref ref-type="bibr" rid="B31">Hair et al., 2014</xref>), reforçando os achados de estudos anteriores acerca da relação entre as variáveis supracitadas (<xref ref-type="bibr" rid="B5">Alotaibi et al., 2020</xref>; <xref ref-type="bibr" rid="B56">Najafi Kalyani et al., 2017</xref>; <xref ref-type="bibr" rid="B65">Sajadi et al., 2014</xref>; <xref ref-type="bibr" rid="B81">Zhabenko et al., 2016</xref>), nesta oportunidade, de maneira hierárquica.</p>
			<p>Na direção de achados anteriores, o DP associou-se a menores níveis de QS na amostra de universitários. De fato, as condições de saúde mental individual implicam em um fator central para a QS das pessoas, sendo tais relações demonstradas por investigações epidemiológicas transversais envolvendo populações adultas (<xref ref-type="bibr" rid="B63">Roberts et al., 2000</xref>). Em populações clínicas, a maior parte dos indivíduos com problemas de saúde mental relatam sono disfuncional e/ou distúrbios do sono, sendo tais sintomatologias a motivação para a procura de assistência profissional (<xref ref-type="bibr" rid="B51">Mendlewicz, 2009</xref>). Conforme indicado, tal padrão, de igual modo, foi replicado no caso dos estudantes universitários apontando que o sofrimento psicológico se associa a situações de déficits na QS (<xref ref-type="bibr" rid="B76">Wang et al., 2019</xref>). Ademais, é importante ressaltar que existem evidências de que problemas do sono e o estado de saúde mental podem apresentar uma relação bidirecional, isto é, um pode ser a causa ou o resultado do outro (<xref ref-type="bibr" rid="B54">Morphy et al., 2007</xref>).</p>
			<p>O EA predisse baixos níveis de QS nos universitários, um achado consistente na literatura médico-psicológica (<xref ref-type="bibr" rid="B5">Alotaibi et al., 2020</xref>; <xref ref-type="bibr" rid="B78">Yan et al., 2018</xref>). Em função das inúmeras tarefas acadêmicas, os universitários frequentemente apresentam problemas de sono, com pouco tempo dedicado ao descanso (<xref ref-type="bibr" rid="B53">Milojevich &amp; Lukowski, 2016</xref>), devido à pressão por alta performance acadêmica (<xref ref-type="bibr" rid="B16">Cardoso et al., 2009</xref>). Tais achados têm um correlato biológico. Especificamente, existem conexões neurais, assim como uma proximidade entre os centros hipotalâmicos reguladores do sono (núcleo supraquiasmático) e estruturas encefálicas envolvidas com respostas autonômicas relacionadas ao estresse (eixo hipotálamo-pituitária-adrenais; <xref ref-type="bibr" rid="B73">Tomfohr et al., 2012</xref>).</p>
			<p>O uso da cafeína, de igual modo, apresentou impactos negativos na QS no modelo estrutural ora testado. Para além de efeitos da cafeína sobre o sistema cardiovascular, tal substância produz efeitos perturbadores no sono, principalmente quando ingerido em doses múltiplas ao longo do dia (<xref ref-type="bibr" rid="B57">Nordt et al., 2012</xref>). Ademais, a cafeína é empregada como um “modelo de insônia”: os efeitos metabólicos da cafeína, de natureza fisiológica, são usados para desenvolver um modelo de excitação fisiológica de insônia crônica em amostras em geral (<xref ref-type="bibr" rid="B12">Bonnet &amp; Arand, 1992</xref>). Quanto ao correlato fisiológico, a secreção de melatonina, o principal hormônio responsável pela sincronização do sono, é controlada por um neurotransmissor que pode ser afetado pela ingestão da cafeína (<xref ref-type="bibr" rid="B67">Shilo et al., 2002</xref>), que por sua vez impacta na QS.</p>
			<p>Finalmente, conforme esperado, baixos níveis de QS predisseram a maior propensão à SD dos universitários. Por exercer funções na restauração, proteção e conservação de energia, quando ocorre uma baixa QS, consequentemente isso se traduz em prejuízos no funcionamento do indivíduo a curto e longo prazo em suas funções físicas, ocupacionais e cognitivas (<xref ref-type="bibr" rid="B55">Müller &amp; Guimarães, 2007</xref>), sendo expressos por SD, isto é, dificuldades na manutenção de se manter alerta, com nível de adequado de excitação fisiológica (<xref ref-type="bibr" rid="B72">Thorpy &amp; Billiard, 2011</xref>). Assevera-se que tal condição, geralmente, está presente em mais da metade dessa população tal como reportam estudos no Brasil com alunos de odontologia (<xref ref-type="bibr" rid="B8">Angelin et al., 2020</xref>), medicina (<xref ref-type="bibr" rid="B53">Milojevich &amp; Lukowski, 2016</xref>), e psicologia (<xref ref-type="bibr" rid="B20">Danda et al., 2005</xref>). Adicionalmente, a fadiga predisse positivamente a SD. De fato, em populações não clínicas, maiores níveis de fadiga estão associados a altas demandas de trabalho e longas jornadas, aqui representadas pelos eventos acadêmicos (<xref ref-type="bibr" rid="B2">Åkerstedt et al., 2014</xref>), que, por sua vez, afetam negativamente a rotina dos estudantes, influenciando no cumprimento de atividades e funções exigidos pelo mundo acadêmico (<xref ref-type="bibr" rid="B80">Zakeri et al., 2006</xref>).</p>
			<p>Entretanto, apesar dos achados descritos, este estudo não está isento de limitações. A primeira refere-se à natureza não probabilística da amostra, fato que impossibilita generalizações dos resultados para a população universitária brasileira. Em seguida, as medidas ora empregadas consistiram em instrumentos de autorrelato, impossibilitando o controle do efeito da desejabilidade social na resposta dos participantes. Por fim, menciona-se o delineamento adotado, correlacional (<italic>ex-post facto</italic>). Apesar de ser possível indicar a existência da relação entre um dado conjunto de variáveis, tal fato não garante a direção (e.g., causalidade reversa) quanto a influência de uma terceira variável no modelo ora testado (<xref ref-type="bibr" rid="B21">Fife-Schaw, 2010</xref>).</p>
			<p>Em resumo, os resultados ora apresentados podem subsidiar intervenções para a população universitária. Em nível político-institucional, as universidades podem se voltar à construção de redes de apoio para comunidade discente (<xref ref-type="bibr" rid="B79">Yusuf et al., 2020</xref>), tais como serviços de atendimento, envolvendo questões como treinos de resiliência frente a estímulos estressores (<xref ref-type="bibr" rid="B32">Hasel et al., 2011</xref>), gerenciamento do tempo em atividades pessoais e acadêmicas (<xref ref-type="bibr" rid="B14">Brus, 2006</xref>) que podem criar condições de uma vivência adaptativa ao meio acadêmico. Nessa direção, estudos futuros podem tanto testar o efeito preditivo de outras variáveis na QS dos universitários (e.g., ansiedade frente ao adormecimento, práticas de higiene do sono etc.), como indicam <xref ref-type="bibr" rid="B13">Brown et al. (2002</xref>) e <xref ref-type="bibr" rid="B3">Al-Kandari et al. (2017</xref>), quanto investigar a efetividade de intervenções práticas com grupos de estudantes universitários de cursos em diferentes áreas de concentração, conforme sugerido por <xref ref-type="bibr" rid="B50">Mendes et al. (2019</xref>) ou diferentes etapas da experiência acadêmica (<xref ref-type="bibr" rid="B70">Soares et al., 2014</xref>).</p>
		</sec>
	</body>
	<back>
		<ref-list>
			<title>Referencias:</title>
			<ref id="B1">
				<mixed-citation>Ackermann, S. &amp; Rasch, B. (2014). Differential effects of non-REM and REM sleep on memory consolidation? <italic>Current Neurology and Neuroscience Reports</italic>, <italic>14</italic>(2),1-10. https://doi.org/10.1007/s11910-013-0430-8</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Ackermann</surname>
							<given-names>S.</given-names>
						</name>
						<name>
							<surname>Rasch</surname>
							<given-names>B.</given-names>
						</name>
					</person-group>
					<year>2014</year>
					<article-title>Differential effects of non-REM and REM sleep on memory consolidation?</article-title>
					<source>Current Neurology and Neuroscience Reports</source>
					<volume>14</volume>
					<issue>2</issue>
					<fpage>1</fpage>
					<lpage>10</lpage>
					<pub-id pub-id-type="doi">10.1007/s11910-013-0430-8</pub-id>
				</element-citation>
			</ref>
			<ref id="B2">
				<mixed-citation>Åkerstedt, T., Axelsson, J., Lekander, M., Orsini, N., &amp; Kecklund, G. (2014). Do sleep, stress, and illness explain daily variations in fatigue? A prospective study. <italic>Journal of Psychosomatic Research</italic>, <italic>76</italic>(4), 280-285. https://doi.org/10.1016/j.jpsychores.2014.01.005</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Åkerstedt</surname>
							<given-names>T.</given-names>
						</name>
						<name>
							<surname>Axelsson</surname>
							<given-names>J.</given-names>
						</name>
						<name>
							<surname>Lekander</surname>
							<given-names>M.</given-names>
						</name>
						<name>
							<surname>Orsini</surname>
							<given-names>N.</given-names>
						</name>
						<name>
							<surname>Kecklund</surname>
							<given-names>G.</given-names>
						</name>
					</person-group>
					<year>2014</year>
					<article-title>Do sleep, stress, and illness explain daily variations in fatigue? A prospective study</article-title>
					<source>Journal of Psychosomatic Research</source>
					<volume>76</volume>
					<issue>4</issue>
					<fpage>280</fpage>
					<lpage>285</lpage>
					<pub-id pub-id-type="doi">10.1016/j.jpsychores.2014.01.005</pub-id>
				</element-citation>
			</ref>
			<ref id="B3">
				<mixed-citation>Al-Kandari, S., Alsalem, A., Al-Mutairi, S., Al-Lumai, D., Dawoud, D., &amp; Moussa, M. (2017). Association between sleep hygiene awareness and practice with sleep quality among Kuwait University students. <italic>Sleep Health</italic>, 3(5), 342-347. https://doi.org/10.1016/j.sleh.2017.06.004</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Al-Kandari</surname>
							<given-names>S.</given-names>
						</name>
						<name>
							<surname>Alsalem</surname>
							<given-names>A.</given-names>
						</name>
						<name>
							<surname>Al-Mutairi</surname>
							<given-names>S.</given-names>
						</name>
						<name>
							<surname>Al-Lumai</surname>
							<given-names>D.</given-names>
						</name>
						<name>
							<surname>Dawoud</surname>
							<given-names>D.</given-names>
						</name>
						<name>
							<surname>Moussa</surname>
							<given-names>M.</given-names>
						</name>
					</person-group>
					<year>2017</year>
					<article-title>Association between sleep hygiene awareness and practice with sleep quality among Kuwait University students</article-title>
					<source>Sleep Health</source>
					<volume>3</volume>
					<issue>5</issue>
					<fpage>342</fpage>
					<lpage>347</lpage>
					<pub-id pub-id-type="doi">10.1016/j.sleh.2017.06.004</pub-id>
				</element-citation>
			</ref>
			<ref id="B4">
				<mixed-citation>Almojali, A. I., Almalki, S. A., Alothman, A. S., Masuadi, E. M., &amp; Alaqeel, M. K. (2017). The prevalence and association of stress with sleep quality among medical students. <italic>Journal of Epidemiology and Global Health</italic>, 7(3), 169-174. http://dx.doi.org/10.1016/j.jegh.2017.04.005</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Almojali</surname>
							<given-names>A. I.</given-names>
						</name>
						<name>
							<surname>Almalki</surname>
							<given-names>S. A.</given-names>
						</name>
						<name>
							<surname>Alothman</surname>
							<given-names>A. S.</given-names>
						</name>
						<name>
							<surname>Masuadi</surname>
							<given-names>E. M.</given-names>
						</name>
						<name>
							<surname>Alaqeel</surname>
							<given-names>M. K.</given-names>
						</name>
					</person-group>
					<year>2017</year>
					<article-title>The prevalence and association of stress with sleep quality among medical students</article-title>
					<source>Journal of Epidemiology and Global Health</source>
					<volume>7</volume>
					<issue>3</issue>
					<fpage>169</fpage>
					<lpage>174</lpage>
					<pub-id pub-id-type="doi">10.1016/j.jegh.2017.04.005</pub-id>
				</element-citation>
			</ref>
			<ref id="B5">
				<mixed-citation>Alotaibi, A. D., Alosaimi, F. M., Alajlan, A. A., &amp; Bin Abdulrahman, K. A. (2020). The relationship between sleep quality, stress, and academic performance among medical students. <italic>Journal of Family &amp; Community Medicine</italic>, <italic>27</italic>(1), 23-28. https://doi.org/10.4103/jfcm.JFCM_132_19</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Alotaibi</surname>
							<given-names>A. D.</given-names>
						</name>
						<name>
							<surname>Alosaimi</surname>
							<given-names>F. M.</given-names>
						</name>
						<name>
							<surname>Alajlan</surname>
							<given-names>A. A.</given-names>
						</name>
						<name>
							<surname>Bin Abdulrahman</surname>
							<given-names>K. A.</given-names>
						</name>
					</person-group>
					<year>2020</year>
					<article-title>The relationship between sleep quality, stress, and academic performance among medical students</article-title>
					<source>Journal of Family &amp; Community Medicine</source>
					<volume>27</volume>
					<issue>1</issue>
					<fpage>23</fpage>
					<lpage>28</lpage>
					<pub-id pub-id-type="doi">10.4103/jfcm.JFCM_132_19</pub-id>
				</element-citation>
			</ref>
			<ref id="B6">
				<mixed-citation>Amaral, A. M. L. (2018). <italic>Qualidade do sono, higiene do sono e temperamento: Um estudo com estudantes universitários portugueses</italic> (Dissertação de mestrado, Universidade de Lisboa). Repositório da Universidade de Lisboa. http://hdl.handle.net/10451/33273</mixed-citation>
				<element-citation publication-type="thesis">
					<person-group person-group-type="author">
						<name>
							<surname>Amaral</surname>
							<given-names>A. M. L.</given-names>
						</name>
					</person-group>
					<year>2018</year>
					<source>Qualidade do sono, higiene do sono e temperamento: Um estudo com estudantes universitários portugueses</source>
					<comment content-type="degree">Dissertação de mestrado</comment>
					<publisher-name>Universidade de Lisboa</publisher-name>
					<comment>Repositório da Universidade de Lisboa</comment>
					<pub-id pub-id-type="doi">10451/33273</pub-id>
				</element-citation>
			</ref>
			<ref id="B7">
				<mixed-citation>Amaro, J. R. M. S. &amp; Dumith, S. C. (2018). Sonolência diurna excessiva e qualidade de vida relacionada à saúde dos professores universitários. <italic>Jornal Brasileiro de Psiquiatria</italic>, <italic>67</italic>(2), 94-100. https://doi.org/10.1590/0047-2085000000191</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Amaro</surname>
							<given-names>J. R. M. S.</given-names>
						</name>
						<name>
							<surname>Dumith</surname>
							<given-names>S. C.</given-names>
						</name>
					</person-group>
					<year>2018</year>
					<article-title>Sonolência diurna excessiva e qualidade de vida relacionada à saúde dos professores universitários</article-title>
					<source>Jornal Brasileiro de Psiquiatria</source>
					<volume>67</volume>
					<issue>2</issue>
					<fpage>94</fpage>
					<lpage>100</lpage>
					<pub-id pub-id-type="doi">10.1590/0047-2085000000191</pub-id>
				</element-citation>
			</ref>
			<ref id="B8">
				<mixed-citation>Angelin, T. J., Mota, K. R., Santos Júnior, V. E., Silva, L., &amp; Heimer, M. V. (2020). Evaluation of sleep quality and daytime sleepiness in dentistry students. <italic>Pesquisa Brasileira em Odontopediatria e Clínica Integrada</italic>, <italic>20</italic>, 1-7. https://doi.org/10.1590/pboci.2020.122</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Angelin</surname>
							<given-names>T. J.</given-names>
						</name>
						<name>
							<surname>Mota</surname>
							<given-names>K. R.</given-names>
						</name>
						<name>
							<surname>Santos</surname>
							<given-names>V. E.</given-names>
							<suffix>Júnior</suffix>
						</name>
						<name>
							<surname>Silva</surname>
							<given-names>L.</given-names>
						</name>
						<name>
							<surname>Heimer</surname>
							<given-names>M. V.</given-names>
						</name>
					</person-group>
					<year>2020</year>
					<article-title>Evaluation of sleep quality and daytime sleepiness in dentistry students</article-title>
					<source>Pesquisa Brasileira em Odontopediatria e Clínica Integrada</source>
					<volume>20</volume>
					<fpage>1</fpage>
					<lpage>7</lpage>
					<pub-id pub-id-type="doi">10.1590/pboci.2020.122</pub-id>
				</element-citation>
			</ref>
			<ref id="B9">
				<mixed-citation>Araújo, M. F. M. D., Lima, A. C. S., Alencar, A. M. P. G., Araújo, T. M. D., Fragoaso, L. V. C., &amp; Damasceno, M. M. C. (2013). Evaluación de la calidad del sueño de estudiantes universitarios de Fortaleza-CE. <italic>Texto &amp; Contexto-Enfermagem</italic>, <italic>22</italic>(2), 352-360. https://doi.org/10.1590/S0104-07072013000200011</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Araújo</surname>
							<given-names>M. F. M. D.</given-names>
						</name>
						<name>
							<surname>Lima</surname>
							<given-names>A. C. S.</given-names>
						</name>
						<name>
							<surname>Alencar</surname>
							<given-names>A. M. P. G.</given-names>
						</name>
						<name>
							<surname>Araújo</surname>
							<given-names>T. M. D.</given-names>
						</name>
						<name>
							<surname>Fragoaso</surname>
							<given-names>L. V. C.</given-names>
						</name>
						<name>
							<surname>Damasceno</surname>
							<given-names>M. M. C.</given-names>
						</name>
					</person-group>
					<year>2013</year>
					<article-title>Evaluación de la calidad del sueño de estudiantes universitarios de Fortaleza-CE</article-title>
					<source>Texto &amp; Contexto-Enfermagem</source>
					<volume>22</volume>
					<issue>2</issue>
					<fpage>352</fpage>
					<lpage>360</lpage>
					<pub-id pub-id-type="doi">10.1590/S0104-07072013000200011</pub-id>
				</element-citation>
			</ref>
			<ref id="B10">
				<mixed-citation>Bertolazi, A. N. (2008). <italic>Tradução, adaptação cultural e validação de dois instrumentos de avaliação do sono: Escala de Sonolência de Epworth e Índice de Qualidade de Sono de Pittsburgh</italic> (Dissertação de doutorado). Universidade Federal do Rio Grande do Sul.</mixed-citation>
				<element-citation publication-type="thesis">
					<person-group person-group-type="author">
						<name>
							<surname>Bertolazi</surname>
							<given-names>A. N.</given-names>
						</name>
					</person-group>
					<year>2008</year>
					<source>Tradução, adaptação cultural e validação de dois instrumentos de avaliação do sono: Escala de Sonolência de Epworth e Índice de Qualidade de Sono de Pittsburgh</source>
					<comment content-type="degree">Dissertação de doutorado</comment>
					<publisher-name>Universidade Federal do Rio Grande do Sul</publisher-name>
				</element-citation>
			</ref>
			<ref id="B11">
				<mixed-citation>Bertolazi, A. N., Fagondes, S. C., Hoff, L. S., Pedro, V. D., Menna Barreto, S. S., &amp; Johns, M. W. (2009). Validação da escala de sonolência de Epworth em português para uso no Brasil. <italic>Jornal Brasileiro de Pneumologia</italic>, <italic>35</italic>(9), 877-883. https://doi.org/10.1590/S1806-37132009000900009</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Bertolazi</surname>
							<given-names>A. N.</given-names>
						</name>
						<name>
							<surname>Fagondes</surname>
							<given-names>S. C.</given-names>
						</name>
						<name>
							<surname>Hoff</surname>
							<given-names>L. S.</given-names>
						</name>
						<name>
							<surname>Pedro</surname>
							<given-names>V. D.</given-names>
						</name>
						<name>
							<surname>Menna Barreto</surname>
							<given-names>S. S.</given-names>
						</name>
						<name>
							<surname>Johns</surname>
							<given-names>M. W.</given-names>
						</name>
					</person-group>
					<year>2009</year>
					<article-title>Validação da escala de sonolência de Epworth em português para uso no Brasil</article-title>
					<source>Jornal Brasileiro de Pneumologia</source>
					<volume>35</volume>
					<issue>9</issue>
					<fpage>877</fpage>
					<lpage>883</lpage>
					<pub-id pub-id-type="doi">10.1590/S1806-37132009000900009</pub-id>
				</element-citation>
			</ref>
			<ref id="B12">
				<mixed-citation>Bonnet, M. H. &amp; Arand, D. L. (1992). Caffeine use as a model of acute and chronic insomnia. <italic>Sleep</italic>, <italic>15</italic>(6), 526-536. https://doi.org/10.1093/sleep/15.6.526</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Bonnet</surname>
							<given-names>M. H.</given-names>
						</name>
						<name>
							<surname>Arand</surname>
							<given-names>D. L.</given-names>
						</name>
					</person-group>
					<year>1992</year>
					<article-title>Caffeine use as a model of acute and chronic insomnia</article-title>
					<source>Sleep</source>
					<volume>15</volume>
					<issue>6</issue>
					<fpage>526</fpage>
					<lpage>536</lpage>
					<pub-id pub-id-type="doi">10.1093/sleep/15.6.526</pub-id>
				</element-citation>
			</ref>
			<ref id="B13">
				<mixed-citation>Brown, F. C., Buboltz Jr, W. C., &amp; Soper, B. (2002). Relationship of sleep hygiene awareness, sleep hygiene practices, and sleep quality in university students. <italic>Behavioral Medicine</italic>, <italic>28</italic>(1), 33-38. http://doi.org/10.1080/08964280209596396</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Brown</surname>
							<given-names>F. C.</given-names>
						</name>
						<name>
							<surname>Buboltz</surname>
							<given-names>W. C.</given-names>
							<suffix>Jr</suffix>
						</name>
						<name>
							<surname>Soper</surname>
							<given-names>B.</given-names>
						</name>
					</person-group>
					<year>2002</year>
					<article-title>Relationship of sleep hygiene awareness, sleep hygiene practices, and sleep quality in university students</article-title>
					<source>Behavioral Medicine</source>
					<volume>28</volume>
					<issue>1</issue>
					<fpage>33</fpage>
					<lpage>38</lpage>
					<pub-id pub-id-type="doi">10.1080/08964280209596396</pub-id>
				</element-citation>
			</ref>
			<ref id="B14">
				<mixed-citation>Brus, C. P. (2006). Seeking balance in graduate school: A realistic expectation or a dangerous dilemma? <italic>New Directions for Student Services</italic>, <italic>2006</italic>(115), 31-45. https://doi.org/10.1002/ss.214</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Brus</surname>
							<given-names>C. P.</given-names>
						</name>
					</person-group>
					<year>2006</year>
					<article-title>Seeking balance in graduate school: A realistic expectation or a dangerous dilemma?</article-title>
					<source>New Directions for Student Services</source>
					<volume>2006</volume>
					<issue>115</issue>
					<fpage>31</fpage>
					<lpage>45</lpage>
					<pub-id pub-id-type="doi">10.1002/ss.214</pub-id>
				</element-citation>
			</ref>
			<ref id="B15">
				<mixed-citation>Buysse, D. J., Reynolds III, C. F., Monk, T. H., Berman, S. R., &amp; Kupfer, D. J. (1989). The Pittsburgh Sleep Quality Index: a new instrument for psychiatric practice and research. <italic>Psychiatry Research</italic>, <italic>28</italic>(2), 193-213. https://doi.org/10.1016/0165-1781(89)90047-4</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Buysse</surname>
							<given-names>D. J.</given-names>
						</name>
						<name>
							<surname>Reynolds III</surname>
							<given-names>C. F.</given-names>
						</name>
						<name>
							<surname>Monk</surname>
							<given-names>T. H.</given-names>
						</name>
						<name>
							<surname>Berman</surname>
							<given-names>S. R.</given-names>
						</name>
						<name>
							<surname>Kupfer</surname>
							<given-names>D. J.</given-names>
						</name>
					</person-group>
					<year>1989</year>
					<article-title>The Pittsburgh Sleep Quality Index: a new instrument for psychiatric practice and research</article-title>
					<source>Psychiatry Research</source>
					<volume>28</volume>
					<issue>2</issue>
					<fpage>193</fpage>
					<lpage>213</lpage>
					<pub-id pub-id-type="doi">10.1016/0165-1781(89)90047-4</pub-id>
				</element-citation>
			</ref>
			<ref id="B16">
				<mixed-citation>Cardoso, H. C., Bueno, F. C. D. C., Mata, J. C. D., Alves, A. P. R., Jochims, I., Vaz Filho, I. H. R., &amp; Hanna, M. M. (2009). Avaliação da qualidade do sono em estudantes de Medicina. <italic>Revista Brasileira de Educação Médica</italic>, <italic>33</italic>(3), 349-355. https://doi.org/10.1590/S0100-55022009000300005</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Cardoso</surname>
							<given-names>H. C.</given-names>
						</name>
						<name>
							<surname>Bueno</surname>
							<given-names>F. C. D. C.</given-names>
						</name>
						<name>
							<surname>Mata</surname>
							<given-names>J. C. D.</given-names>
						</name>
						<name>
							<surname>Alves</surname>
							<given-names>A. P. R.</given-names>
						</name>
						<name>
							<surname>Jochims</surname>
							<given-names>I.</given-names>
						</name>
						<name>
							<surname>Vaz</surname>
							<given-names>I. H. R.</given-names>
							<suffix>Filho</suffix>
						</name>
						<name>
							<surname>Hanna</surname>
							<given-names>M. M.</given-names>
						</name>
					</person-group>
					<year>2009</year>
					<article-title>Avaliação da qualidade do sono em estudantes de Medicina</article-title>
					<source>Revista Brasileira de Educação Médica</source>
					<volume>33</volume>
					<issue>3</issue>
					<fpage>349</fpage>
					<lpage>355</lpage>
					<pub-id pub-id-type="doi">10.1590/S0100-55022009000300005</pub-id>
				</element-citation>
			</ref>
			<ref id="B17">
				<mixed-citation>Cheng, S. H., Shih, C.-C., Lee, I. H., Hou, Y.-W., Chen, K. C., Chen, K.-T., Yang, Y. K., &amp; Yang, Y. C. (2012). A study on the sleep quality of incoming university students. <italic>Psychiatry Research</italic>, <italic>197</italic>(3), 270-274. https://doi.org/10.1016/j.psychres.2011.08.011</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Cheng</surname>
							<given-names>S. H.</given-names>
						</name>
						<name>
							<surname>Shih</surname>
							<given-names>C.-C.</given-names>
						</name>
						<name>
							<surname>Lee</surname>
							<given-names>I. H.</given-names>
						</name>
						<name>
							<surname>Hou</surname>
							<given-names>Y.-W.</given-names>
						</name>
						<name>
							<surname>Chen</surname>
							<given-names>K. C.</given-names>
						</name>
						<name>
							<surname>Chen</surname>
							<given-names>K.-T.</given-names>
						</name>
						<name>
							<surname>Yang</surname>
							<given-names>Y. K.</given-names>
						</name>
						<name>
							<surname>Yang</surname>
							<given-names>Y. C.</given-names>
						</name>
					</person-group>
					<year>2012</year>
					<article-title>A study on the sleep quality of incoming university students</article-title>
					<source>Psychiatry Research</source>
					<volume>197</volume>
					<issue>3</issue>
					<fpage>270</fpage>
					<lpage>274</lpage>
					<pub-id pub-id-type="doi">10.1016/j.psychres.2011.08.011</pub-id>
				</element-citation>
			</ref>
			<ref id="B18">
				<mixed-citation>Christodoulou, N., Maruani, J., d’Ortho, M. -P., Lejoyeux, M., &amp; Geoffroy, P.A. (2023). Sleep quality of medical students and relationships with academic performances. <italic>L'Encéphale</italic>, <italic>49</italic>(1), 9-14. https://doi.org/10.1016/j.encep.2021.09.006</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Christodoulou</surname>
							<given-names>N.</given-names>
						</name>
						<name>
							<surname>Maruani</surname>
							<given-names>J.</given-names>
						</name>
						<name>
							<surname>d’Ortho</surname>
							<given-names>M. -P.</given-names>
						</name>
						<name>
							<surname>Lejoyeux</surname>
							<given-names>M.</given-names>
						</name>
						<name>
							<surname>Geoffroy</surname>
							<given-names>P.A.</given-names>
						</name>
					</person-group>
					<year>2023</year>
					<article-title>Sleep quality of medical students and relationships with academic performances</article-title>
					<source>L'Encéphale</source>
					<volume>49</volume>
					<issue>1</issue>
					<fpage>9</fpage>
					<lpage>14</lpage>
					<pub-id pub-id-type="doi">doi.org/10.1016/j.encep.2021.09.006</pub-id>
				</element-citation>
			</ref>
			<ref id="B19">
				<mixed-citation>Curcio, G., Ferrara, M., &amp; De Gennaro, L. (2006). Sleep loss, learning capacity and academic performance. <italic>Sleep Medicine Reviews</italic>, <italic>10</italic>(5), 323-337. https://doi.org/10.1016/j.smrv.2005.11.001</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Curcio</surname>
							<given-names>G.</given-names>
						</name>
						<name>
							<surname>Ferrara</surname>
							<given-names>M.</given-names>
						</name>
						<name>
							<surname>De Gennaro</surname>
							<given-names>L.</given-names>
						</name>
					</person-group>
					<year>2006</year>
					<article-title>Sleep loss, learning capacity and academic performance</article-title>
					<source>Sleep Medicine Reviews</source>
					<volume>10</volume>
					<issue>5</issue>
					<fpage>323</fpage>
					<lpage>337</lpage>
					<pub-id pub-id-type="doi">10.1016/j.smrv.2005.11.001</pub-id>
				</element-citation>
			</ref>
			<ref id="B20">
				<mixed-citation>Danda, G. D. N., Ferreira, G. R., Azenha, M., Souza, K. D., &amp; Bastos, O. (2005). Sleep-wake cycle pattern and excessive daytime sleepiness in medical students. <italic>Jornal Brasileiro de Psiquiatria</italic>, <italic>54</italic>(2), 102-106. </mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Danda</surname>
							<given-names>G. D. N.</given-names>
						</name>
						<name>
							<surname>Ferreira</surname>
							<given-names>G. R.</given-names>
						</name>
						<name>
							<surname>Azenha</surname>
							<given-names>M.</given-names>
						</name>
						<name>
							<surname>Souza</surname>
							<given-names>K. D.</given-names>
						</name>
						<name>
							<surname>Bastos</surname>
							<given-names>O.</given-names>
						</name>
					</person-group>
					<year>2005</year>
					<article-title>Sleep-wake cycle pattern and excessive daytime sleepiness in medical students</article-title>
					<source>Jornal Brasileiro de Psiquiatria</source>
					<volume>54</volume>
					<issue>2</issue>
					<fpage>102</fpage>
					<lpage>106</lpage>
				</element-citation>
			</ref>
			<ref id="B21">
				<mixed-citation>Fife-Schaw, C. (2010). Modelos quasi-experimentais. Em G. M. Breakwell., S, Hammond., J. A. Smith &amp; V. G. Haase (Eds.), <italic>Métodos de pesquisa em</italic> psicologia (pp. 100-115). Artmed.</mixed-citation>
				<element-citation publication-type="book">
					<person-group person-group-type="author">
						<name>
							<surname>Fife-Schaw</surname>
							<given-names>C.</given-names>
						</name>
					</person-group>
					<year>2010</year>
					<chapter-title>Modelos quasi-experimentais</chapter-title>
					<person-group person-group-type="editor">
						<name>
							<surname>Breakwell</surname>
							<given-names>G. M.</given-names>
						</name>
						<name>
							<surname>Hammond</surname>
							<given-names>S</given-names>
						</name>
						<name>
							<surname>Smith</surname>
							<given-names>J. A.</given-names>
						</name>
						<name>
							<surname>Haase</surname>
							<given-names>V. G.</given-names>
						</name>
					</person-group>
					<source><italic>Métodos de pesquisa em</italic> psicologia</source>
					<fpage>100</fpage>
					<lpage>115</lpage>
					<publisher-name>Artmed</publisher-name>
				</element-citation>
			</ref>
			<ref id="B22">
				<mixed-citation>Fonseca, A. G. &amp; Genzel, L. (2020). Sleep and academic performance: considering amount, quality and timing. <italic>Current Opinion in Behavioral Sciences</italic>, <italic>33</italic>, 65-71. https://doi.org/10.1016/j.cobeha.2019.12.008</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Fonseca</surname>
							<given-names>A. G.</given-names>
						</name>
						<name>
							<surname>Genzel</surname>
							<given-names>L.</given-names>
						</name>
					</person-group>
					<year>2020</year>
					<article-title>Sleep and academic performance: considering amount, quality and timing</article-title>
					<source>Current Opinion in Behavioral Sciences</source>
					<volume>33</volume>
					<fpage>65</fpage>
					<lpage>71</lpage>
					<pub-id pub-id-type="doi">10.1016/j.cobeha.2019.12.008</pub-id>
				</element-citation>
			</ref>
			<ref id="B23">
				<mixed-citation>Fox, J. (2017). <italic>Using the R Commander</italic>: A Point-and-Click Interface or R. Chapman and Hall/CRC Press.</mixed-citation>
				<element-citation publication-type="book">
					<person-group person-group-type="author">
						<name>
							<surname>Fox</surname>
							<given-names>J.</given-names>
						</name>
					</person-group>
					<year>2017</year>
					<source>Using the R Commander</source>
					<publisher-name>A Point-and-Click Interface or R. Chapman and Hall/CRC Press</publisher-name>
				</element-citation>
			</ref>
			<ref id="B24">
				<mixed-citation>Freires, L. A., Sousa, E. A., Loureto, G. D. L., Monteiro, R. P., &amp; Gouveia, V. V. (2018). Estresse acadêmico: adaptação e evidências psicométricas de uma medida. <italic>Psicologia em Pesquisa</italic>, <italic>12</italic>(3), 22-32. https://dx.doi.org/10.24879/2018001200300532</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Freires</surname>
							<given-names>L. A.</given-names>
						</name>
						<name>
							<surname>Sousa</surname>
							<given-names>E. A.</given-names>
						</name>
						<name>
							<surname>Loureto</surname>
							<given-names>G. D. L.</given-names>
						</name>
						<name>
							<surname>Monteiro</surname>
							<given-names>R. P.</given-names>
						</name>
						<name>
							<surname>Gouveia</surname>
							<given-names>V. V.</given-names>
						</name>
					</person-group>
					<year>2018</year>
					<article-title>Estresse acadêmico: adaptação e evidências psicométricas de uma medida</article-title>
					<source>Psicologia em Pesquisa</source>
					<volume>12</volume>
					<issue>3</issue>
					<fpage>22</fpage>
					<lpage>32</lpage>
					<pub-id pub-id-type="doi">10.24879/2018001200300532</pub-id>
				</element-citation>
			</ref>
			<ref id="B25">
				<mixed-citation>Fujii, H., Fukuda, S., Narumi, D., Ihara, T., &amp; Watanabe, Y. (2015). Fatigue and sleep under large summer temperature differences. <italic>Environmental Research</italic>, <italic>138</italic>, 17-21. https://doi.org/10.1016/j.envres.2015.02.006</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Fujii</surname>
							<given-names>H.</given-names>
						</name>
						<name>
							<surname>Fukuda</surname>
							<given-names>S.</given-names>
						</name>
						<name>
							<surname>Narumi</surname>
							<given-names>D.</given-names>
						</name>
						<name>
							<surname>Ihara</surname>
							<given-names>T.</given-names>
						</name>
						<name>
							<surname>Watanabe</surname>
							<given-names>Y.</given-names>
						</name>
					</person-group>
					<year>2015</year>
					<article-title>Fatigue and sleep under large summer temperature differences</article-title>
					<source>Environmental Research</source>
					<volume>138</volume>
					<fpage>17</fpage>
					<lpage>21</lpage>
					<pub-id pub-id-type="doi">10.1016/j.envres.2015.02.006</pub-id>
				</element-citation>
			</ref>
			<ref id="B26">
				<mixed-citation>García, N. B. &amp; Zea, R. M. (2011). Estrés Académico. <italic>Revista de Psicología Universidad Antioquia</italic>, 3(2), 65-82. </mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>García</surname>
							<given-names>N. B.</given-names>
						</name>
						<name>
							<surname>Zea</surname>
							<given-names>R. M.</given-names>
						</name>
					</person-group>
					<year>2011</year>
					<article-title>Estrés Académico</article-title>
					<source>Revista de Psicología Universidad Antioquia</source>
					<volume>3</volume>
					<issue>2</issue>
					<fpage>65</fpage>
					<lpage>82</lpage>
				</element-citation>
			</ref>
			<ref id="B27">
				<mixed-citation>García-Ros, R., Pérez-González, F., Pérez-Blasco, J., &amp; Natividad, L. A. (2012). Evaluación del estrés académico en estudiantes de nueva incorporación a la universidad. <italic>Revista Latinoamericana de Psicología</italic>, <italic>44</italic>(2), 143-154. </mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>García-Ros</surname>
							<given-names>R.</given-names>
						</name>
						<name>
							<surname>Pérez-González</surname>
							<given-names>F.</given-names>
						</name>
						<name>
							<surname>Pérez-Blasco</surname>
							<given-names>J.</given-names>
						</name>
						<name>
							<surname>Natividad</surname>
							<given-names>L. A.</given-names>
						</name>
					</person-group>
					<year>2012</year>
					<article-title>Evaluación del estrés académico en estudiantes de nueva incorporación a la universidad</article-title>
					<source>Revista Latinoamericana de Psicología</source>
					<volume>44</volume>
					<issue>2</issue>
					<fpage>143</fpage>
					<lpage>154</lpage>
				</element-citation>
			</ref>
			<ref id="B28">
				<mixed-citation>Gardiner, C., Weakley, J., Burke, L. M., Roach, G. D., Sargent, C., Maniar, N., Townshend, A., &amp; Halson, S. L. (2023). The effect of caffeine on subsequent sleep: A systematic review and meta-analysis. <italic>Sleep Medicine Reviews</italic>, <italic>69</italic>, 101764. http://doi.org/10.1016/j.smrv.2023.101764</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Gardiner</surname>
							<given-names>C.</given-names>
						</name>
						<name>
							<surname>Weakley</surname>
							<given-names>J.</given-names>
						</name>
						<name>
							<surname>Burke</surname>
							<given-names>L. M.</given-names>
						</name>
						<name>
							<surname>Roach</surname>
							<given-names>G. D.</given-names>
						</name>
						<name>
							<surname>Sargent</surname>
							<given-names>C.</given-names>
						</name>
						<name>
							<surname>Maniar</surname>
							<given-names>N.</given-names>
						</name>
						<name>
							<surname>Townshend</surname>
							<given-names>A.</given-names>
						</name>
						<name>
							<surname>Halson</surname>
							<given-names>S. L.</given-names>
						</name>
					</person-group>
					<year>2023</year>
					<article-title>The effect of caffeine on subsequent sleep: A systematic review and meta-analysis</article-title>
					<source>Sleep Medicine Reviews</source>
					<volume>69</volume>
					<elocation-id>101764</elocation-id>
					<pub-id pub-id-type="doi">10.1016/j.smrv.2023.101764</pub-id>
				</element-citation>
			</ref>
			<ref id="B29">
				<mixed-citation>Gillin, J. C., Drummond, S. P. A., Clark, C. P., &amp; Moore, P. (2005). Medication and substance abuse. Em M. H. Krygier, T. Roth &amp; W. C. Dement (Eds.), <italic>Principles and Practice of Sleep Medicine</italic> (4<sup>a</sup> ed., pp. 1345-1358). Saunders.</mixed-citation>
				<element-citation publication-type="book">
					<person-group person-group-type="author">
						<name>
							<surname>Gillin</surname>
							<given-names>J. C.</given-names>
						</name>
						<name>
							<surname>Drummond</surname>
							<given-names>S. P. A.</given-names>
						</name>
						<name>
							<surname>Clark</surname>
							<given-names>C. P.</given-names>
						</name>
						<name>
							<surname>Moore</surname>
							<given-names>P.</given-names>
						</name>
					</person-group>
					<year>2005</year>
					<chapter-title>Medication and substance abuse</chapter-title>
					<person-group person-group-type="editor">
						<name>
							<surname>Krygier</surname>
							<given-names>M. H.</given-names>
						</name>
						<name>
							<surname>Roth</surname>
							<given-names>T.</given-names>
						</name>
						<name>
							<surname>Dement</surname>
							<given-names>W. C.</given-names>
						</name>
					</person-group>
					<source>Principles and Practice of Sleep Medicine</source>
					<edition>4a ed.</edition>
					<fpage>1345</fpage>
					<lpage>1358</lpage>
					<publisher-name>Saunders</publisher-name>
				</element-citation>
			</ref>
			<ref id="B30">
				<mixed-citation>Goldberg, D. (1972). <italic>The Detection of Psychiatric Illness by Questionnarie</italic>. Oxford United Press.</mixed-citation>
				<element-citation publication-type="book">
					<person-group person-group-type="author">
						<name>
							<surname>Goldberg</surname>
							<given-names>D.</given-names>
						</name>
					</person-group>
					<year>1972</year>
					<source>The Detection of Psychiatric Illness by Questionnarie</source>
					<publisher-name>Oxford United Press</publisher-name>
				</element-citation>
			</ref>
			<ref id="B31">
				<mixed-citation>Hair, Jr., Black, W. C., Babin, B. J., &amp; Anderson, R. E. (2014). <italic>Multivariate Data Analysis</italic> (7<sup>a</sup> ed.). Pearson Education Limited.</mixed-citation>
				<element-citation publication-type="book">
					<person-group person-group-type="author">
						<name>
							<surname>Hair</surname>
							<given-names>Jr.</given-names>
						</name>
						<name>
							<surname>Black</surname>
							<given-names>W. C.</given-names>
						</name>
						<name>
							<surname>Babin</surname>
							<given-names>B. J.</given-names>
						</name>
						<name>
							<surname>Anderson</surname>
							<given-names>R. E.</given-names>
						</name>
					</person-group>
					<year>2014</year>
					<source>Multivariate Data Analysis</source>
					<edition>7a ed.</edition>
					<publisher-name>Pearson Education Limited</publisher-name>
				</element-citation>
			</ref>
			<ref id="B32">
				<mixed-citation>Hasel, K. M., Abdolhoseini, A., &amp; Ganji, P. (2011). Hardiness training and perceived stress among college students. <italic>Procedia-Social and Behavioral Sciences</italic>, <italic>30</italic>, 1354-1358. http://doi.org/10.1016/j.sbspro.2011.10.262</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Hasel</surname>
							<given-names>K. M.</given-names>
						</name>
						<name>
							<surname>Abdolhoseini</surname>
							<given-names>A.</given-names>
						</name>
						<name>
							<surname>Ganji</surname>
							<given-names>P.</given-names>
						</name>
					</person-group>
					<year>2011</year>
					<article-title>Hardiness training and perceived stress among college students</article-title>
					<source>Procedia-Social and Behavioral Sciences</source>
					<volume>30</volume>
					<fpage>1354</fpage>
					<lpage>1358</lpage>
					<pub-id pub-id-type="doi">10.1016/j.sbspro.2011.10.262</pub-id>
				</element-citation>
			</ref>
			<ref id="B33">
				<mixed-citation>Hayes, A. F. (2017). <italic>Introduction to mediation, moderation, and conditional process analysis: A regression-based approach</italic>. Guilford Publications.</mixed-citation>
				<element-citation publication-type="book">
					<person-group person-group-type="author">
						<name>
							<surname>Hayes</surname>
							<given-names>A. F.</given-names>
						</name>
					</person-group>
					<year>2017</year>
					<source>Introduction to mediation, moderation, and conditional process analysis: A regression-based approach</source>
					<publisher-name>Guilford Publications</publisher-name>
				</element-citation>
			</ref>
			<ref id="B34">
				<mixed-citation>Henriques, A. P. F. C. M. (2008). <italic>Caracterização do sono dos estudantes universitários do Instituto Superior Técnico</italic> (Dissertação de mestrado). Universidade de Lisboa.</mixed-citation>
				<element-citation publication-type="thesis">
					<person-group person-group-type="author">
						<name>
							<surname>Henriques</surname>
							<given-names>A. P. F. C. M.</given-names>
						</name>
					</person-group>
					<year>2008</year>
					<source>Caracterização do sono dos estudantes universitários do Instituto Superior Técnico</source>
					<comment content-type="degree">Dissertação de mestrado</comment>
					<publisher-name>Universidade de Lisboa</publisher-name>
				</element-citation>
			</ref>
			<ref id="B35">
				<mixed-citation>Huang, C. F., Yang, L. Y., Wu, L. M., Liu, Y., &amp; Chen, H. M. (2014). Determinants of daytime sleepiness in first-year nursing students: a questionnaire survey. <italic>Nurse education today</italic>, <italic>34</italic>(6), 1048-1053. http://doi.org/10.1016/j.nedt.2013.11.005</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Huang</surname>
							<given-names>C. F.</given-names>
						</name>
						<name>
							<surname>Yang</surname>
							<given-names>L. Y.</given-names>
						</name>
						<name>
							<surname>Wu</surname>
							<given-names>L. M.</given-names>
						</name>
						<name>
							<surname>Liu</surname>
							<given-names>Y.</given-names>
						</name>
						<name>
							<surname>Chen</surname>
							<given-names>H. M.</given-names>
						</name>
					</person-group>
					<year>2014</year>
					<article-title>Determinants of daytime sleepiness in first-year nursing students: a questionnaire survey</article-title>
					<source>Nurse education today</source>
					<volume>34</volume>
					<issue>6</issue>
					<fpage>1048</fpage>
					<lpage>1053</lpage>
					<pub-id pub-id-type="doi">10.1016/j.nedt.2013.11.005</pub-id>
				</element-citation>
			</ref>
			<ref id="B36">
				<mixed-citation>Johns, M. W. (1991). A new method for measuring daytime sleepiness: the Epworth sleepiness scale. S<italic>leep</italic>, <italic>14</italic>(6), 540-545. https://doi.org/10.1093/sleep/14.6.540</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Johns</surname>
							<given-names>M. W.</given-names>
						</name>
					</person-group>
					<year>1991</year>
					<article-title>A new method for measuring daytime sleepiness: the Epworth sleepiness scale</article-title>
					<source>Sleep</source>
					<volume>14</volume>
					<issue>6</issue>
					<fpage>540</fpage>
					<lpage>545</lpage>
					<pub-id pub-id-type="doi">10.1093/sleep/14.6.540</pub-id>
				</element-citation>
			</ref>
			<ref id="B37">
				<mixed-citation>Kaneita, Y., Yokoyama, E., Harano, S., Tamaki, T., Suzuki, H., Munezawa, T., Nakajima, H., Asai, T., &amp; Ohida, T. (2009). Associations between sleep disturbance and mental health status: A longitudinal study of Japanese junior high school students. <italic>Sleep Medicine</italic>, <italic>10</italic>(7), 780-786. https://doi.org/10.1016/j.sleep.2008.06.014</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Kaneita</surname>
							<given-names>Y.</given-names>
						</name>
						<name>
							<surname>Yokoyama</surname>
							<given-names>E.</given-names>
						</name>
						<name>
							<surname>Harano</surname>
							<given-names>S.</given-names>
						</name>
						<name>
							<surname>Tamaki</surname>
							<given-names>T.</given-names>
						</name>
						<name>
							<surname>Suzuki</surname>
							<given-names>H.</given-names>
						</name>
						<name>
							<surname>Munezawa</surname>
							<given-names>T.</given-names>
						</name>
						<name>
							<surname>Nakajima</surname>
							<given-names>H.</given-names>
						</name>
						<name>
							<surname>Asai</surname>
							<given-names>T.</given-names>
						</name>
						<name>
							<surname>Ohida</surname>
							<given-names>T.</given-names>
						</name>
					</person-group>
					<year>2009</year>
					<article-title>Associations between sleep disturbance and mental health status: A longitudinal study of Japanese junior high school students</article-title>
					<source>Sleep Medicine</source>
					<volume>10</volume>
					<issue>7</issue>
					<fpage>780</fpage>
					<lpage>786</lpage>
					<pub-id pub-id-type="doi">10.1016/j.sleep.2008.06.014</pub-id>
				</element-citation>
			</ref>
			<ref id="B38">
				<mixed-citation>Kaur, F. &amp; Singh, A. (2017). Excessive daytime sleepiness and its pattern among Indian college students. <italic>Sleep Medicine</italic>, 29, 23-28. https://doi.org/10.1016/j.sleep.2016.08.020</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Kaur</surname>
							<given-names>F.</given-names>
						</name>
						<name>
							<surname>Singh</surname>
							<given-names>A.</given-names>
						</name>
					</person-group>
					<year>2017</year>
					<article-title>Excessive daytime sleepiness and its pattern among Indian college students</article-title>
					<source>Sleep Medicine</source>
					<volume>29</volume>
					<fpage>23</fpage>
					<lpage>28</lpage>
					<pub-id pub-id-type="doi">10.1016/j.sleep.2016.08.020</pub-id>
				</element-citation>
			</ref>
			<ref id="B39">
				<mixed-citation>Koohsari, M. J., Nakaya, T., McCormack, G. R., Shibata, A., Ishii, K., &amp; Oka, K. (2021). Changes in workers' sedentary and physical activity behaviors in response to the COVID-19 pandemic and their relationships with fatigue: longitudinal online study. <italic>JMIR Public Health and Surveillance</italic>, 7(3), e26293. https://doi.org/10.2196/26293</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Koohsari</surname>
							<given-names>M. J.</given-names>
						</name>
						<name>
							<surname>Nakaya</surname>
							<given-names>T.</given-names>
						</name>
						<name>
							<surname>McCormack</surname>
							<given-names>G. R.</given-names>
						</name>
						<name>
							<surname>Shibata</surname>
							<given-names>A.</given-names>
						</name>
						<name>
							<surname>Ishii</surname>
							<given-names>K.</given-names>
						</name>
						<name>
							<surname>Oka</surname>
							<given-names>K.</given-names>
						</name>
					</person-group>
					<year>2021</year>
					<article-title>Changes in workers' sedentary and physical activity behaviors in response to the COVID-19 pandemic and their relationships with fatigue: longitudinal online study</article-title>
					<source>JMIR Public Health and Surveillance</source>
					<volume>7</volume>
					<issue>3</issue>
					<elocation-id>e26293</elocation-id>
					<pub-id pub-id-type="doi">10.2196/26293</pub-id>
				</element-citation>
			</ref>
			<ref id="B40">
				<mixed-citation>Landmann, N., Kuhn, M., Piosczyk, H., Feige, B., Baglioni, C., Spiegelhalder, K., Frase, L., Riemann, D., Sterr. A., &amp; Nissen, C. (2014). The reorganisation of memory during sleep. <italic>Sleep Medicine Reviews</italic>, <italic>18</italic>(6), 531-541. https://doi.org/10.1016/j.smrv.2014.03.005</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Landmann</surname>
							<given-names>N.</given-names>
						</name>
						<name>
							<surname>Kuhn</surname>
							<given-names>M.</given-names>
						</name>
						<name>
							<surname>Piosczyk</surname>
							<given-names>H.</given-names>
						</name>
						<name>
							<surname>Feige</surname>
							<given-names>B.</given-names>
						</name>
						<name>
							<surname>Baglioni</surname>
							<given-names>C.</given-names>
						</name>
						<name>
							<surname>Spiegelhalder</surname>
							<given-names>K.</given-names>
						</name>
						<name>
							<surname>Frase</surname>
							<given-names>L.</given-names>
						</name>
						<name>
							<surname>Riemann</surname>
							<given-names>D.</given-names>
						</name>Sterr. A.<name>
							<surname>Nissen</surname>
							<given-names>C.</given-names>
						</name>
					</person-group>
					<year>2014</year>
					<article-title>The reorganisation of memory during sleep</article-title>
					<source>Sleep Medicine Reviews</source>
					<volume>18</volume>
					<issue>6</issue>
					<fpage>531</fpage>
					<lpage>541</lpage>
					<pub-id pub-id-type="doi">10.1016/j.smrv.2014.03.005</pub-id>
				</element-citation>
			</ref>
			<ref id="B41">
				<mixed-citation>Lazarus, R. S. &amp; Folkman, S. (1984). <italic>Stress, appraisal, and coping</italic>. Springer.</mixed-citation>
				<element-citation publication-type="book">
					<person-group person-group-type="author">
						<name>
							<surname>Lazarus</surname>
							<given-names>R. S.</given-names>
						</name>
						<name>
							<surname>Folkman</surname>
							<given-names>S.</given-names>
						</name>
					</person-group>
					<year>1984</year>
					<source>Stress, appraisal, and coping</source>
					<publisher-name>Springer</publisher-name>
				</element-citation>
			</ref>
			<ref id="B42">
				<mixed-citation>Lemma, S., Gelaye, B., Berhane, Y., Worku, A., &amp; Williams, M. A. (2012). Sleep quality and its psychological correlates among university students in Ethiopia: a cross-sectional study. <italic>BMC psychiatry</italic>, <italic>12</italic>(1), 1-7. https://doi.org/10.1186/1471-244X-12-237</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Lemma</surname>
							<given-names>S.</given-names>
						</name>
						<name>
							<surname>Gelaye</surname>
							<given-names>B.</given-names>
						</name>
						<name>
							<surname>Berhane</surname>
							<given-names>Y.</given-names>
						</name>
						<name>
							<surname>Worku</surname>
							<given-names>A.</given-names>
						</name>
						<name>
							<surname>Williams</surname>
							<given-names>M. A.</given-names>
						</name>
					</person-group>
					<year>2012</year>
					<article-title>Sleep quality and its psychological correlates among university students in Ethiopia: a cross-sectional study</article-title>
					<source>BMC psychiatry</source>
					<volume>12</volume>
					<issue>1</issue>
					<fpage>1</fpage>
					<lpage>7</lpage>
					<pub-id pub-id-type="doi">10.1186/1471-244X-12-237</pub-id>
				</element-citation>
			</ref>
			<ref id="B43">
				<mixed-citation>Li, L., Wang, Y., Wang, S., Li L., Lu, L., Ng, C. H., Ungvari, G. S., Chiu, H. F. K, Hou, C., Jia, F. &amp; Xiang, Y. (2017). Sleep Duration and Sleep Patterns in Chinese University Students: A Comprehensive Meta-Analysis. <italic>Journal of Clinical Sleep Medicine</italic>, <italic>13</italic>(10), 1153-1162. https://doi.org/10.5664/jcsm.6760</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Li</surname>
							<given-names>L.</given-names>
						</name>
						<name>
							<surname>Wang</surname>
							<given-names>Y.</given-names>
						</name>
						<name>
							<surname>Wang</surname>
							<given-names>S.</given-names>
						</name>
						<name>
							<surname>Li</surname>
							<given-names>L.</given-names>
						</name>
						<name>
							<surname>Lu</surname>
							<given-names>L.</given-names>
						</name>
						<name>
							<surname>Ng</surname>
							<given-names>C. H.</given-names>
						</name>
						<name>
							<surname>Ungvari</surname>
							<given-names>G. S.</given-names>
						</name>
						<name>
							<surname>Chiu</surname>
							<given-names>H. F. K</given-names>
						</name>
						<name>
							<surname>Hou</surname>
							<given-names>C.</given-names>
						</name>
						<name>
							<surname>Jia</surname>
							<given-names>F.</given-names>
						</name>
						<name>
							<surname>Xiang</surname>
							<given-names>Y.</given-names>
						</name>
					</person-group>
					<year>2017</year>
					<article-title>Sleep Duration and Sleep Patterns in Chinese University Students: A Comprehensive Meta-Analysis</article-title>
					<source>Journal of Clinical Sleep Medicine</source>
					<volume>13</volume>
					<issue>10</issue>
					<fpage>1153</fpage>
					<lpage>1162</lpage>
					<pub-id pub-id-type="doi">10.5664/jcsm.6760</pub-id>
				</element-citation>
			</ref>
			<ref id="B44">
				<mixed-citation>Lopes, E., Milheiro, I., &amp; Maia, A. (2013). Sleep quality in college students: a study about the contribution of lifestyle, academic performance and general well-being. <italic>Sleep Medicine</italic>, <italic>14</italic>(1). https://doi.org/10.1016/j.sleep.2013.11.437</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Lopes</surname>
							<given-names>E.</given-names>
						</name>
						<name>
							<surname>Milheiro</surname>
							<given-names>I.</given-names>
						</name>
						<name>
							<surname>Maia</surname>
							<given-names>A.</given-names>
						</name>
					</person-group>
					<year>2013</year>
					<article-title>Sleep quality in college students: a study about the contribution of lifestyle, academic performance and general well-being</article-title>
					<source>Sleep Medicine</source>
					<volume>14</volume>
					<issue>1</issue>
					<pub-id pub-id-type="doi">10.1016/j.sleep.2013.11.437</pub-id>
				</element-citation>
			</ref>
			<ref id="B45">
				<mixed-citation>Lund, H. G., Reider, B. D., Whiting, A. B., &amp; Prichard, J. R. (2010). Sleep patterns and predictors of disturbed sleep in a large population of college students. <italic>Journal of Adolescent Health</italic>, <italic>46</italic>(2), 124-132. https://doi.org/10.1016/j.jadohealth.2009.06.016</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Lund</surname>
							<given-names>H. G.</given-names>
						</name>
						<name>
							<surname>Reider</surname>
							<given-names>B. D.</given-names>
						</name>
						<name>
							<surname>Whiting</surname>
							<given-names>A. B.</given-names>
						</name>
						<name>
							<surname>Prichard</surname>
							<given-names>J. R.</given-names>
						</name>
					</person-group>
					<year>2010</year>
					<article-title>Sleep patterns and predictors of disturbed sleep in a large population of college students</article-title>
					<source>Journal of Adolescent Health</source>
					<volume>46</volume>
					<issue>2</issue>
					<fpage>124</fpage>
					<lpage>132</lpage>
					<pub-id pub-id-type="doi">j.jadohealth.2009.06.016</pub-id>
				</element-citation>
			</ref>
			<ref id="B46">
				<mixed-citation>Madras, B. &amp; Kuhar, M. (Eds.). (2013). <italic>The effects of drug abuse on the human nervous system</italic>. Elsevier.</mixed-citation>
				<element-citation publication-type="book">
					<person-group person-group-type="editor">
						<name>
							<surname>Madras</surname>
							<given-names>B.</given-names>
						</name>
						<name>
							<surname>Kuhar</surname>
							<given-names>M.</given-names>
						</name>
					</person-group>
					<year>2013</year>
					<source>The effects of drug abuse on the human nervous system</source>
					<publisher-name>Elsevier</publisher-name>
				</element-citation>
			</ref>
			<ref id="B47">
				<mixed-citation>Mariño, M. C., González-Forteza, C., Andrade, P., &amp; Medina-Mora, M. E. (1998). Validación de un cuestionario para detectar adolescentes con problemas por el uso de drogas. <italic>Salud mental</italic>, <italic>21</italic>(1), 27-36.</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Mariño</surname>
							<given-names>M. C.</given-names>
						</name>
						<name>
							<surname>González-Forteza</surname>
							<given-names>C.</given-names>
						</name>
						<name>
							<surname>Andrade</surname>
							<given-names>P.</given-names>
						</name>
						<name>
							<surname>Medina-Mora</surname>
							<given-names>M. E.</given-names>
						</name>
					</person-group>
					<year>1998</year>
					<article-title>Validación de un cuestionario para detectar adolescentes con problemas por el uso de drogas</article-title>
					<source>Salud mental</source>
					<volume>21</volume>
					<issue>1</issue>
					<fpage>27</fpage>
					<lpage>36</lpage>
				</element-citation>
			</ref>
			<ref id="B48">
				<mixed-citation>Marôco, J. &amp; Garcia-Marques, T. (2006). Qual a fiabilidade do alfa de Cronbach? Questões antigas e soluções modernas? <italic>Laboratório de psicologia</italic>, 4(1), 65-90. https://doi.org/10.14417/lp.763</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Marôco</surname>
							<given-names>J.</given-names>
						</name>
						<name>
							<surname>Garcia-Marques</surname>
							<given-names>T.</given-names>
						</name>
					</person-group>
					<year>2006</year>
					<article-title>Qual a fiabilidade do alfa de Cronbach? Questões antigas e soluções modernas?</article-title>
					<source>Laboratório de psicologia</source>
					<volume>4</volume>
					<issue>1</issue>
					<fpage>65</fpage>
					<lpage>90</lpage>
					<pub-id pub-id-type="doi">10.14417/lp.763</pub-id>
				</element-citation>
			</ref>
			<ref id="B49">
				<mixed-citation>Massud, M., Barbosa, G. A., &amp; Gouveia, V. V. (2007). Indicadores de saúde mental. Em G. A. Barbosa (Coord.), <italic>A saúde dos médicos no Brasil</italic> (pp. 143-157). Conselho Federal de Medicina.</mixed-citation>
				<element-citation publication-type="book">
					<person-group person-group-type="author">
						<name>
							<surname>Massud</surname>
							<given-names>M.</given-names>
						</name>
						<name>
							<surname>Barbosa</surname>
							<given-names>G. A.</given-names>
						</name>
						<name>
							<surname>Gouveia</surname>
							<given-names>V. V.</given-names>
						</name>
					</person-group>
					<year>2007</year>
					<chapter-title>Indicadores de saúde mental</chapter-title>
					<person-group person-group-type="author">
						<name>
							<surname>Barbosa</surname>
							<given-names>G. A.</given-names>
						</name>
					</person-group>
					<source>A saúde dos médicos no Brasil</source>
					<fpage>143</fpage>
					<lpage>157</lpage>
					<publisher-name>Conselho Federal de Medicina</publisher-name>
				</element-citation>
			</ref>
			<ref id="B50">
				<mixed-citation>Mendes, J., Sousa, M., Leite, V. M., Belchior, N., &amp; Medeiros, T. (2019). Qualidade do sono e sonolência em estudantes do ensino superior. <italic>Revista Portuguesa de Investigação Comportamental e Social</italic>, 5(2), 38-48. https://doi.org/10.31211/rpics.2019.5.2.150</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Mendes</surname>
							<given-names>J.</given-names>
						</name>
						<name>
							<surname>Sousa</surname>
							<given-names>M.</given-names>
						</name>
						<name>
							<surname>Leite</surname>
							<given-names>V. M.</given-names>
						</name>
						<name>
							<surname>Belchior</surname>
							<given-names>N.</given-names>
						</name>
						<name>
							<surname>Medeiros</surname>
							<given-names>T.</given-names>
						</name>
					</person-group>
					<year>2019</year>
					<article-title>Qualidade do sono e sonolência em estudantes do ensino superior</article-title>
					<source>Revista Portuguesa de Investigação Comportamental e Social</source>
					<volume>5</volume>
					<issue>2</issue>
					<fpage>38</fpage>
					<lpage>48</lpage>
					<pub-id pub-id-type="doi">10.31211/rpics.2019.5.2.150</pub-id>
				</element-citation>
			</ref>
			<ref id="B51">
				<mixed-citation>Mendlewicz, J. (2009). Sleep disturbances: core symptoms of major depressive disorder rather than associated or comorbid disorders. <italic>The World Journal of Biological Psychiatry</italic>, <italic>10</italic>(4), 269-275. https://doi.org/10.3109/15622970802503086</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Mendlewicz</surname>
							<given-names>J.</given-names>
						</name>
					</person-group>
					<year>2009</year>
					<article-title>Sleep disturbances: core symptoms of major depressive disorder rather than associated or comorbid disorders</article-title>
					<source>The World Journal of Biological Psychiatry</source>
					<volume>10</volume>
					<issue>4</issue>
					<fpage>269</fpage>
					<lpage>275</lpage>
					<pub-id pub-id-type="doi">10.3109/15622970802503086</pub-id>
				</element-citation>
			</ref>
			<ref id="B52">
				<mixed-citation>Michielsen, H. J., De Vries, J., Van Heck, G. L., Van de Vijver, F. J., &amp; Sijtsma, K. (2004). Examination of the dimensionality of fatigue. The construction of the Fatigue Assessment Scale (FAS). <italic>European Journal of Psychological Assessment</italic>, <italic>20</italic>(1), 39-48. https://doi.org/10.1027/1015-5759.20.1.39</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Michielsen</surname>
							<given-names>H. J.</given-names>
						</name>
						<name>
							<surname>De Vries</surname>
							<given-names>J.</given-names>
						</name>
						<name>
							<surname>Van Heck</surname>
							<given-names>G. L.</given-names>
						</name>
						<name>
							<surname>Van de Vijver</surname>
							<given-names>F. J.</given-names>
						</name>
						<name>
							<surname>Sijtsma</surname>
							<given-names>K.</given-names>
						</name>
					</person-group>
					<year>2004</year>
					<article-title>Examination of the dimensionality of fatigue. The construction of the Fatigue Assessment Scale (FAS)</article-title>
					<source>European Journal of Psychological Assessment</source>
					<volume>20</volume>
					<issue>1</issue>
					<fpage>39</fpage>
					<lpage>48</lpage>
					<pub-id pub-id-type="doi">10.1027/1015-5759.20.1.39</pub-id>
				</element-citation>
			</ref>
			<ref id="B53">
				<mixed-citation>Milojevich, H. M. &amp; Lukowski, A. F. (2016). Sleep and mental health in undergraduate students with generally healthy sleep habits. <italic>PloS one</italic>, <italic>11</italic>(6), 1-14. http://doi.org/10.1371/journal.pone.0156372</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Milojevich</surname>
							<given-names>H. M.</given-names>
						</name>
						<name>
							<surname>Lukowski</surname>
							<given-names>A. F.</given-names>
						</name>
					</person-group>
					<year>2016</year>
					<article-title>Sleep and mental health in undergraduate students with generally healthy sleep habits</article-title>
					<source>PloS one</source>
					<volume>11</volume>
					<issue>6</issue>
					<fpage>1</fpage>
					<lpage>14</lpage>
					<pub-id pub-id-type="doi">10.1371/journal.pone.0156372</pub-id>
				</element-citation>
			</ref>
			<ref id="B54">
				<mixed-citation>Morphy, H., Dunn, K. M., Lewis, M., Boardman, H. F., &amp; Croft, P. R. (2007). Epidemiology of insomnia: a longitudinal study in a UK population. <italic>Sleep</italic>, <italic>30</italic>(3), 274-280. https://doi.org/10.1093/sleep/30.3.274</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Morphy</surname>
							<given-names>H.</given-names>
						</name>
						<name>
							<surname>Dunn</surname>
							<given-names>K. M.</given-names>
						</name>
						<name>
							<surname>Lewis</surname>
							<given-names>M.</given-names>
						</name>
						<name>
							<surname>Boardman</surname>
							<given-names>H. F.</given-names>
						</name>
						<name>
							<surname>Croft</surname>
							<given-names>P. R.</given-names>
						</name>
					</person-group>
					<year>2007</year>
					<article-title>Epidemiology of insomnia: a longitudinal study in a UK population</article-title>
					<source>Sleep</source>
					<volume>30</volume>
					<issue>3</issue>
					<fpage>274</fpage>
					<lpage>280</lpage>
					<pub-id pub-id-type="doi">10.1093/sleep/30.3.274</pub-id>
				</element-citation>
			</ref>
			<ref id="B55">
				<mixed-citation>Müller, M. R. &amp; Guimarães, S. S. (2007). Sleep disorders impact on daily functioning and life quality. <italic>Estudos de Psicologia</italic>, <italic>24</italic>(4), 519-528. https://doi.org/10.1590/S0103-166X2007000400011</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Müller</surname>
							<given-names>M. R.</given-names>
						</name>
						<name>
							<surname>Guimarães</surname>
							<given-names>S. S.</given-names>
						</name>
					</person-group>
					<year>2007</year>
					<article-title>Sleep disorders impact on daily functioning and life quality</article-title>
					<source>Estudos de Psicologia</source>
					<volume>24</volume>
					<issue>4</issue>
					<fpage>519</fpage>
					<lpage>528</lpage>
					<pub-id pub-id-type="doi">10.1590/S0103-166X2007000400011</pub-id>
				</element-citation>
			</ref>
			<ref id="B56">
				<mixed-citation>Najafi Kalyani, M., Jamshidi, N., Salami, J., &amp; Pourjam, E. (2017). Investigation of the relationship between psychological variables and sleep quality in students of medical sciences. <italic>Depression Research and Treatment</italic>, <italic>2017</italic>, 1-6. https://doi.org/10.1155/2017/7143547</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Najafi Kalyani</surname>
							<given-names>M.</given-names>
						</name>
						<name>
							<surname>Jamshidi</surname>
							<given-names>N.</given-names>
						</name>
						<name>
							<surname>Salami</surname>
							<given-names>J.</given-names>
						</name>
						<name>
							<surname>Pourjam</surname>
							<given-names>E.</given-names>
						</name>
					</person-group>
					<year>2017</year>
					<article-title>Investigation of the relationship between psychological variables and sleep quality in students of medical sciences</article-title>
					<source>Depression Research and Treatment</source>
					<volume>2017</volume>
					<fpage>1</fpage>
					<lpage>6</lpage>
					<pub-id pub-id-type="doi">10.1155/2017/7143547</pub-id>
				</element-citation>
			</ref>
			<ref id="B57">
				<mixed-citation>Nordt, S. P., Vilke, G. M., Clark, R. F., Cantrell, F. L., Chan, T. C., Galinato, M., Nguyen, V. &amp; Castillo, E. M. (2012). Energy drink use and adverse effects among emergency department patients. <italic>Journal of community health</italic>, <italic>37</italic>(5), 976-981. https://doi.org/10.1007/s10900-012-9549-9</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Nordt</surname>
							<given-names>S. P.</given-names>
						</name>
						<name>
							<surname>Vilke</surname>
							<given-names>G. M.</given-names>
						</name>
						<name>
							<surname>Clark</surname>
							<given-names>R. F.</given-names>
						</name>
						<name>
							<surname>Cantrell</surname>
							<given-names>F. L.</given-names>
						</name>
						<name>
							<surname>Chan</surname>
							<given-names>T. C.</given-names>
						</name>
						<name>
							<surname>Galinato</surname>
							<given-names>M.</given-names>
						</name>
						<name>
							<surname>Nguyen</surname>
							<given-names>V.</given-names>
						</name>
						<name>
							<surname>Castillo</surname>
							<given-names>E. M.</given-names>
						</name>
					</person-group>
					<year>2012</year>
					<article-title>Energy drink use and adverse effects among emergency department patients</article-title>
					<source>Journal of community health</source>
					<volume>37</volume>
					<issue>5</issue>
					<fpage>976</fpage>
					<lpage>981</lpage>
					<pub-id pub-id-type="doi">10.1007/s10900-012-9549-9</pub-id>
				</element-citation>
			</ref>
			<ref id="B58">
				<mixed-citation>Panjwani, U., Wadhwa, M., Ray, K., &amp; Kishore, K. (2019). Sleep deprivation, cognitive functions, and countermeasures. Em S. K. Jha &amp; V. M. Jha (Eds.), <italic>Sleep, memory and synaptic plasticity</italic> (pp. 41-56). Springer.</mixed-citation>
				<element-citation publication-type="book">
					<person-group person-group-type="author">
						<name>
							<surname>Panjwani</surname>
							<given-names>U.</given-names>
						</name>
						<name>
							<surname>Wadhwa</surname>
							<given-names>M.</given-names>
						</name>
						<name>
							<surname>Ray</surname>
							<given-names>K.</given-names>
						</name>
						<name>
							<surname>Kishore</surname>
							<given-names>K.</given-names>
						</name>
					</person-group>
					<year>2019</year>
					<chapter-title>Sleep deprivation, cognitive functions, and countermeasures</chapter-title>
					<person-group person-group-type="editor">
						<name>
							<surname>Jha</surname>
							<given-names>S. K.</given-names>
						</name>
						<name>
							<surname>Jha</surname>
							<given-names>V. M.</given-names>
						</name>
					</person-group>
					<source>Sleep, memory and synaptic plasticity</source>
					<fpage>41</fpage>
					<lpage>56</lpage>
					<publisher-name>Springer</publisher-name>
				</element-citation>
			</ref>
			<ref id="B59">
				<mixed-citation>Paschoal, T. &amp; Tamayo, Á. (2004). Validação da escala de estresse no trabalho. <italic>Estudos de Psicologia</italic>, 9(1), 45-52. https://doi.org/10.1590/S1413-294X2004000100006</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Paschoal</surname>
							<given-names>T.</given-names>
						</name>
						<name>
							<surname>Tamayo</surname>
							<given-names>Á.</given-names>
						</name>
					</person-group>
					<year>2004</year>
					<article-title>Validação da escala de estresse no trabalho</article-title>
					<source>Estudos de Psicologia</source>
					<volume>9</volume>
					<issue>1</issue>
					<fpage>45</fpage>
					<lpage>52</lpage>
					<pub-id pub-id-type="doi">10.1590/S1413-294X2004000100006</pub-id>
				</element-citation>
			</ref>
			<ref id="B60">
				<mixed-citation>Phillips, A. J. K., Clerx, W. M., O’Brien, C. S., Sano, A., Barger, L. K., Picard, R. W., Lockley, S. W., Klerman, E. B. &amp; Czeisler, C. A. (2017). Irregular sleep/wake patterns are associated with poorer academic performance and delayed circadian and sleep/wake timing. <italic>Scientific Reports</italic>, 7(1), 1-13. https://doi.org/10.1038/s41598-017-03171-4</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Phillips</surname>
							<given-names>A. J. K.</given-names>
						</name>
						<name>
							<surname>Clerx</surname>
							<given-names>W. M.</given-names>
						</name>
						<name>
							<surname>O’Brien</surname>
							<given-names>C. S.</given-names>
						</name>
						<name>
							<surname>Sano</surname>
							<given-names>A.</given-names>
						</name>
						<name>
							<surname>Barger</surname>
							<given-names>L. K.</given-names>
						</name>
						<name>
							<surname>Picard</surname>
							<given-names>R. W.</given-names>
						</name>
						<name>
							<surname>Lockley</surname>
							<given-names>S. W.</given-names>
						</name>
						<name>
							<surname>Klerman</surname>
							<given-names>E. B.</given-names>
						</name>
						<name>
							<surname>Czeisler</surname>
							<given-names>C. A.</given-names>
						</name>
					</person-group>
					<year>2017</year>
					<article-title>Irregular sleep/wake patterns are associated with poorer academic performance and delayed circadian and sleep/wake timing</article-title>
					<source>Scientific Reports</source>
					<volume>7</volume>
					<issue>1</issue>
					<fpage>1</fpage>
					<lpage>13</lpage>
					<pub-id pub-id-type="doi">10.1038/s41598-017-03171-4</pub-id>
				</element-citation>
			</ref>
			<ref id="B61">
				<mixed-citation>R Development Core Team. (2015). <italic>R: A language and environment for statistical computing</italic> (Version 4.3.1). <ext-link ext-link-type="uri" xlink:href="https://cran.r-project.org/doc/manuals/fullrefman.pdf">https://cran.r-project.org/doc/manuals/fullrefman.pdf</ext-link>
				</mixed-citation>
				<element-citation publication-type="book">
					<person-group person-group-type="author">
						<collab>R Development Core Team</collab>
					</person-group>
					<year>2015</year>
					<source>R: A language and environment for statistical computing</source>
					<ext-link ext-link-type="uri" xlink:href="https://cran.r-project.org/doc/manuals/fullrefman.pdf">https://cran.r-project.org/doc/manuals/fullrefman.pdf</ext-link>
				</element-citation>
			</ref>
			<ref id="B62">
				<mixed-citation>Rasch, B. &amp; Born, J. (2015). In search of a role of REM sleep in memory formation (Editorial). <italic>Neurobiology of Learning and Memory</italic>, <italic>122</italic>, 1-3. https://doi.org/10.1016/j.nlm.2015.04.012</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Rasch</surname>
							<given-names>B.</given-names>
						</name>
						<name>
							<surname>Born</surname>
							<given-names>J.</given-names>
						</name>
					</person-group>
					<year>2015</year>
					<article-title>In search of a role of REM sleep in memory formation (Editorial)</article-title>
					<source>Neurobiology of Learning and Memory</source>
					<volume>122</volume>
					<fpage>1</fpage>
					<lpage>3</lpage>
					<pub-id pub-id-type="doi">10.1016/j.nlm.2015.04.012</pub-id>
				</element-citation>
			</ref>
			<ref id="B63">
				<mixed-citation>Roberts, R. E., Shema, S. J., Kaplan, G. A., &amp; Strawbridge, W. J. (2000). Sleep complaints and depression in an aging cohort: a prospective perspective. <italic>American Journal of Psychiatry</italic>, <italic>157</italic>(1), 81-88. https://doi.org/10.1176/ajp.157.1.81</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Roberts</surname>
							<given-names>R. E.</given-names>
						</name>
						<name>
							<surname>Shema</surname>
							<given-names>S. J.</given-names>
						</name>
						<name>
							<surname>Kaplan</surname>
							<given-names>G. A.</given-names>
						</name>
						<name>
							<surname>Strawbridge</surname>
							<given-names>W. J.</given-names>
						</name>
					</person-group>
					<year>2000</year>
					<article-title>Sleep complaints and depression in an aging cohort: a prospective perspective</article-title>
					<source>American Journal of Psychiatry</source>
					<volume>157</volume>
					<issue>1</issue>
					<fpage>81</fpage>
					<lpage>88</lpage>
					<pub-id pub-id-type="doi">https://doi.org/10.1176/ajp.157.1.81</pub-id>
				</element-citation>
			</ref>
			<ref id="B64">
				<mixed-citation>Rosseel, Y. (2012). Lavaan: An R Package for Structural Equation Modeling. <italic>Journal of Statistical Software</italic>, <italic>48</italic>(2), 1-36. http://doi.org/10.18637/jss.v048.i02</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Rosseel</surname>
							<given-names>Y.</given-names>
						</name>
					</person-group>
					<year>2012</year>
					<article-title>Lavaan: An R Package for Structural Equation Modeling</article-title>
					<source>Journal of Statistical Software</source>
					<volume>48</volume>
					<issue>2</issue>
					<fpage>1</fpage>
					<lpage>36</lpage>
					<pub-id pub-id-type="doi">10.18637/jss.v048.i02</pub-id>
				</element-citation>
			</ref>
			<ref id="B65">
				<mixed-citation>Sajadi, A., Farsi, Z., &amp; Rajai, N. (2014). The relationship between sleep quality with fatigue severity and academic performance of nursing students. <italic>Nursing Practice Today</italic>, 1(4), 213-220. </mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Sajadi</surname>
							<given-names>A.</given-names>
						</name>
						<name>
							<surname>Farsi</surname>
							<given-names>Z.</given-names>
						</name>
						<name>
							<surname>Rajai</surname>
							<given-names>N.</given-names>
						</name>
					</person-group>
					<year>2014</year>
					<article-title>The relationship between sleep quality with fatigue severity and academic performance of nursing students</article-title>
					<source>Nursing Practice Today</source>
					<volume>1</volume>
					<issue>4</issue>
					<fpage>213</fpage>
					<lpage>220</lpage>
				</element-citation>
			</ref>
			<ref id="B66">
				<mixed-citation>Schreiber, J. B., Nora, A., Stage, F. K., Barlow, E. A., &amp; King, J. (2006). Reporting structural equation modeling and confirmatory factor analysis results: A review. <italic>The Journal of Educational Research</italic>, <italic>99</italic>(6), 323-338. https://doi.org/10.3200/JOER.99.6.323-338</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Schreiber</surname>
							<given-names>J. B.</given-names>
						</name>
						<name>
							<surname>Nora</surname>
							<given-names>A.</given-names>
						</name>
						<name>
							<surname>Stage</surname>
							<given-names>F. K.</given-names>
						</name>
						<name>
							<surname>Barlow</surname>
							<given-names>E. A.</given-names>
						</name>
						<name>
							<surname>King</surname>
							<given-names>J.</given-names>
						</name>
					</person-group>
					<year>2006</year>
					<article-title>Reporting structural equation modeling and confirmatory factor analysis results: A review</article-title>
					<source>The Journal of Educational Research</source>
					<volume>99</volume>
					<issue>6</issue>
					<fpage>323</fpage>
					<lpage>338</lpage>
					<pub-id pub-id-type="doi">10.3200/JOER.99.6.323-338</pub-id>
				</element-citation>
			</ref>
			<ref id="B67">
				<mixed-citation>Shilo, L., Sabbah, H., Hadari, R., Kovatz, S., Weinberg, U., Dolev, S., Dagan, Y. &amp; Shenkman, L. (2002). The effects of coffee consumption on sleep and melatonin secretion. <italic>Sleep Medicine</italic>, 3(3), 271-273. https://doi.org/10.1016/S1389-9457(02)00015-1</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Shilo</surname>
							<given-names>L.</given-names>
						</name>
						<name>
							<surname>Sabbah</surname>
							<given-names>H.</given-names>
						</name>
						<name>
							<surname>Hadari</surname>
							<given-names>R.</given-names>
						</name>
						<name>
							<surname>Kovatz</surname>
							<given-names>S.</given-names>
						</name>
						<name>
							<surname>Weinberg</surname>
							<given-names>U.</given-names>
						</name>
						<name>
							<surname>Dolev</surname>
							<given-names>S.</given-names>
						</name>
						<name>
							<surname>Dagan</surname>
							<given-names>Y.</given-names>
						</name>
						<name>
							<surname>Shenkman</surname>
							<given-names>L.</given-names>
						</name>
					</person-group>
					<year>2002</year>
					<article-title>The effects of coffee consumption on sleep and melatonin secretion</article-title>
					<source>Sleep Medicine</source>
					<volume>3</volume>
					<issue>3</issue>
					<fpage>271</fpage>
					<lpage>273</lpage>
					<pub-id pub-id-type="doi">10.1016/S1389-9457(02)00015-1</pub-id>
				</element-citation>
			</ref>
			<ref id="B68">
				<mixed-citation>Shrout, P. E. &amp; Bolger, N. (2002). Mediation in experimental and nonexperimental studies: new procedures and recommendations. <italic>Psychological Methods</italic>, 7(4), 422. https://doi.org/10.1037/1082-989X.7.4.422</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Shrout</surname>
							<given-names>P. E.</given-names>
						</name>
						<name>
							<surname>Bolger</surname>
							<given-names>N.</given-names>
						</name>
					</person-group>
					<year>2002</year>
					<article-title>Mediation in experimental and nonexperimental studies: new procedures and recommendations</article-title>
					<source>Psychological Methods</source>
					<volume>7</volume>
					<issue>4</issue>
					<fpage>422</fpage>
					<lpage>422</lpage>
					<pub-id pub-id-type="doi">10.1037/1082-989X.7.4.422</pub-id>
				</element-citation>
			</ref>
			<ref id="B69">
				<mixed-citation>Sin, C. W., Ho, J. S., &amp; Chung, J. W. (2009). Systematic review on the effectiveness of caffeine abstinence on the quality of sleep. <italic>Journal of Clinical Nursing</italic>, <italic>18</italic>(1), 13-21. https://doi.org/10.1111/j.1365-2702.2008.02375.x</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Sin</surname>
							<given-names>C. W.</given-names>
						</name>
						<name>
							<surname>Ho</surname>
							<given-names>J. S.</given-names>
						</name>
						<name>
							<surname>Chung</surname>
							<given-names>J. W.</given-names>
						</name>
					</person-group>
					<year>2009</year>
					<article-title>Systematic review on the effectiveness of caffeine abstinence on the quality of sleep</article-title>
					<source>Journal of Clinical Nursing</source>
					<volume>18</volume>
					<issue>1</issue>
					<fpage>13</fpage>
					<lpage>21</lpage>
					<pub-id pub-id-type="doi">10.1111/j.1365-2702.2008.02375.x</pub-id>
				</element-citation>
			</ref>
			<ref id="B70">
				<mixed-citation>Soares, A. M., Pereira, M., &amp; Canavarro, J. P. (2014). Saúde e qualidade de vid ana transição para o Ensino Superior. <italic>Psicologia, Saúde &amp; Doenças</italic>, <italic>15</italic>(2), 356-379. http://dx.doi.org/10.15309/14psd150204</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Soares</surname>
							<given-names>A. M.</given-names>
						</name>
						<name>
							<surname>Pereira</surname>
							<given-names>M.</given-names>
						</name>
						<name>
							<surname>Canavarro</surname>
							<given-names>J. P.</given-names>
						</name>
					</person-group>
					<year>2014</year>
					<article-title>Saúde e qualidade de vid ana transição para o Ensino Superior</article-title>
					<source>Psicologia, Saúde &amp; Doenças</source>
					<volume>15</volume>
					<issue>2</issue>
					<fpage>356</fpage>
					<lpage>379</lpage>
					<pub-id pub-id-type="doi">10.15309/14psd150204</pub-id>
				</element-citation>
			</ref>
			<ref id="B71">
				<mixed-citation>Suzuki, H., Kaneita, Y., Osaki, Y., Minowa, M., Kanda, H., Suzuki, K., Wada, K., Hayashi, K., Tanihata, T &amp; Ohida, T. (2011). Clarification of the factor structure of the 12-item General Health Questionnaire among Japanese adolescents and associated sleep status. <italic>Psychiatry research</italic>, <italic>188</italic>(1), 138-146. https://doi.org/10.1016/j.psychres.2010.10.025</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Suzuki</surname>
							<given-names>H.</given-names>
						</name>
						<name>
							<surname>Kaneita</surname>
							<given-names>Y.</given-names>
						</name>
						<name>
							<surname>Osaki</surname>
							<given-names>Y.</given-names>
						</name>
						<name>
							<surname>Minowa</surname>
							<given-names>M.</given-names>
						</name>
						<name>
							<surname>Kanda</surname>
							<given-names>H.</given-names>
						</name>
						<name>
							<surname>Suzuki</surname>
							<given-names>K.</given-names>
						</name>
						<name>
							<surname>Wada</surname>
							<given-names>K.</given-names>
						</name>
						<name>
							<surname>Hayashi</surname>
							<given-names>K.</given-names>
						</name>
						<name>
							<surname>Tanihata</surname>
							<given-names>T</given-names>
						</name>
						<name>
							<surname>Ohida</surname>
							<given-names>T.</given-names>
						</name>
					</person-group>
					<year>2011</year>
					<article-title>Clarification of the factor structure of the 12-item General Health Questionnaire among Japanese adolescents and associated sleep status</article-title>
					<source>Psychiatry research</source>
					<volume>188</volume>
					<issue>1</issue>
					<fpage>138</fpage>
					<lpage>146</lpage>
					<pub-id pub-id-type="doi">10.1016/j.psychres.2010.10.025</pub-id>
				</element-citation>
			</ref>
			<ref id="B72">
				<mixed-citation>Thorpy, M. J. &amp; Billiard, M. (Eds.). (2011). <italic>Sleepiness: causes, consequences and treatment</italic>. Cambridge University Press.</mixed-citation>
				<element-citation publication-type="book">
					<person-group person-group-type="editor">
						<name>
							<surname>Thorpy</surname>
							<given-names>M. J.</given-names>
						</name>
						<name>
							<surname>Billiard</surname>
							<given-names>M.</given-names>
						</name>
					</person-group>
					<year>2011</year>
					<source>Sleepiness: causes, consequences and treatment</source>
					<publisher-name>Cambridge University Press</publisher-name>
				</element-citation>
			</ref>
			<ref id="B73">
				<mixed-citation>Tomfohr, L. M., Edwards, K. M., &amp; Dimsdale, J. E. (2012). Is obstructive sleep apnea associated with cortisol levels? A systematic review of the research evidence. <italic>Sleep Medicine Reviews</italic>, <italic>16</italic>(3), 243-249. https://doi.org/10.1016/j.smrv.2011.05.003</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Tomfohr</surname>
							<given-names>L. M.</given-names>
						</name>
						<name>
							<surname>Edwards</surname>
							<given-names>K. M.</given-names>
						</name>
						<name>
							<surname>Dimsdale</surname>
							<given-names>J. E.</given-names>
						</name>
					</person-group>
					<year>2012</year>
					<article-title>Is obstructive sleep apnea associated with cortisol levels? A systematic review of the research evidence</article-title>
					<source>Sleep Medicine Reviews</source>
					<volume>16</volume>
					<issue>3</issue>
					<fpage>243</fpage>
					<lpage>249</lpage>
					<pub-id pub-id-type="doi">10.1016/j.smrv.2011.05.003</pub-id>
				</element-citation>
			</ref>
			<ref id="B74">
				<mixed-citation>Tsai, S. C. &amp; Lee-Chiong, T. (2013). Sleep disorders and fatigue. <italic>Sleep Medicine Clinics</italic>, 8(2), 235-239. https://doi.org/10.1016/j.jsmc.2013.02.003</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Tsai</surname>
							<given-names>S. C.</given-names>
						</name>
						<name>
							<surname>Lee-Chiong</surname>
							<given-names>T.</given-names>
						</name>
					</person-group>
					<year>2013</year>
					<article-title>Sleep disorders and fatigue</article-title>
					<source>Sleep Medicine Clinics</source>
					<volume>8</volume>
					<issue>2</issue>
					<fpage>235</fpage>
					<lpage>239</lpage>
					<pub-id pub-id-type="doi">10.1016/j.jsmc.2013.02.003</pub-id>
				</element-citation>
			</ref>
			<ref id="B75">
				<mixed-citation>Wang, F. &amp; Bíró, É. (2021). Determinants of sleep quality in college students: a literature review. <italic>Explore</italic>, <italic>17</italic>(2), 170-177. https://doi.org/10.1016/j.explore.2020.11.003</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Wang</surname>
							<given-names>F.</given-names>
						</name>
						<name>
							<surname>Bíró</surname>
							<given-names>É.</given-names>
						</name>
					</person-group>
					<year>2021</year>
					<article-title>Determinants of sleep quality in college students: a literature review</article-title>
					<source>Explore</source>
					<volume>17</volume>
					<issue>2</issue>
					<fpage>170</fpage>
					<lpage>177</lpage>
					<pub-id pub-id-type="doi">10.1016/j.explore.2020.11.003</pub-id>
				</element-citation>
			</ref>
			<ref id="B76">
				<mixed-citation>Wang, K., Xue, Y., Fan, X., Huang, T., &amp; Chen, Z. (2019). Sedentary behaviors, psychological status, and sleep quality in Chinese university students. <italic>Social Behavior and Personality</italic>, <italic>47</italic>(1), 1-10. https://doi.org/10.2224/sbp.7446</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Wang</surname>
							<given-names>K.</given-names>
						</name>
						<name>
							<surname>Xue</surname>
							<given-names>Y.</given-names>
						</name>
						<name>
							<surname>Fan</surname>
							<given-names>X.</given-names>
						</name>
						<name>
							<surname>Huang</surname>
							<given-names>T.</given-names>
						</name>
						<name>
							<surname>Chen</surname>
							<given-names>Z.</given-names>
						</name>
					</person-group>
					<year>2019</year>
					<article-title>Sedentary behaviors, psychological status, and sleep quality in Chinese university students</article-title>
					<source>Social Behavior and Personality</source>
					<volume>47</volume>
					<issue>1</issue>
					<fpage>1</fpage>
					<lpage>10</lpage>
					<pub-id pub-id-type="doi">10.2224/sbp.7446</pub-id>
				</element-citation>
			</ref>
			<ref id="B77">
				<mixed-citation>Wylie, G. R., Pra Sisto, A. J., Genova, H. M., &amp; DeLuca, J. (2022). Fatigue across the lifespan in men and women: State vs. trait. <italic>Frontiers in Human Neuroscience</italic>, <italic>16</italic>, 790006. https://doi.org/10.3389/fnhum.2022.790006</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Wylie</surname>
							<given-names>G. R.</given-names>
						</name>
						<name>
							<surname>Pra Sisto</surname>
							<given-names>A. J.</given-names>
						</name>
						<name>
							<surname>Genova</surname>
							<given-names>H. M.</given-names>
						</name>
						<name>
							<surname>DeLuca</surname>
							<given-names>J.</given-names>
						</name>
					</person-group>
					<year>2022</year>
					<article-title>Fatigue across the lifespan in men and women: State vs. trait</article-title>
					<source>Frontiers in Human Neuroscience</source>
					<volume>16</volume>
					<elocation-id>790006</elocation-id>
					<pub-id pub-id-type="doi">10.3389/fnhum.2022.790006</pub-id>
				</element-citation>
			</ref>
			<ref id="B78">
				<mixed-citation>Yan, Y., Lin, R., &amp; Su, Y. (2018). The relationship between adolescent academic stress and sleep quality: a multiple mediation model. <italic>Social Behavior and Personality</italic>, <italic>46</italic>(1<italic>),</italic> 
 <italic>63-78</italic>. https://doi.org/10.2224/sbp.6530</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Yan</surname>
							<given-names>Y.</given-names>
						</name>
						<name>
							<surname>Lin</surname>
							<given-names>R.</given-names>
						</name>
						<name>
							<surname>Su</surname>
							<given-names>Y.</given-names>
						</name>
					</person-group>
					<year>2018</year>
					<article-title>The relationship between adolescent academic stress and sleep quality: a multiple mediation model</article-title>
					<source>Social Behavior and Personality</source>
					<volume>46</volume>
					<issue>1</issue>
					<fpage>63</fpage>
					<lpage>78</lpage>
					<pub-id pub-id-type="doi">10.2224/sbp.6530</pub-id>
				</element-citation>
			</ref>
			<ref id="B79">
				<mixed-citation>Yusuf, J. E., Saitgalina, M., &amp; Chapman, D. W. (2020). Work-life balance and well-being of graduate students. <italic>Journal of Public Affairs Education</italic>, <italic>26</italic>(4), 458-483. https://doi.org/10.1080/15236803.2020.1771990</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Yusuf</surname>
							<given-names>J. E.</given-names>
						</name>
						<name>
							<surname>Saitgalina</surname>
							<given-names>M.</given-names>
						</name>
						<name>
							<surname>Chapman</surname>
							<given-names>D. W.</given-names>
						</name>
					</person-group>
					<year>2020</year>
					<article-title>Work-life balance and well-being of graduate students</article-title>
					<source>Journal of Public Affairs Education</source>
					<volume>26</volume>
					<issue>4</issue>
					<fpage>458</fpage>
					<lpage>483</lpage>
					<pub-id pub-id-type="doi">10.1080/15236803.2020.1771990</pub-id>
				</element-citation>
			</ref>
			<ref id="B80">
				<mixed-citation>Zakeri, M., Shaban, M., Kazemnezhad, A., &amp; Tavassoli, K. (2006). Effect of exercise utilizing the rate of respiratory on fatigue in patient with chronic obstructive pulmonary disease. <italic>Hayat</italic>, 3(30), 17-25. </mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Zakeri</surname>
							<given-names>M.</given-names>
						</name>
						<name>
							<surname>Shaban</surname>
							<given-names>M.</given-names>
						</name>
						<name>
							<surname>Kazemnezhad</surname>
							<given-names>A.</given-names>
						</name>
						<name>
							<surname>Tavassoli</surname>
							<given-names>K.</given-names>
						</name>
					</person-group>
					<year>2006</year>
					<article-title>Effect of exercise utilizing the rate of respiratory on fatigue in patient with chronic obstructive pulmonary disease</article-title>
					<source>Hayat</source>
					<volume>3</volume>
					<issue>30</issue>
					<fpage>17</fpage>
					<lpage>25</lpage>
				</element-citation>
			</ref>
			<ref id="B81">
				<mixed-citation>Zhabenko, O., Austic, E., Conroy, D. A., Ehrlich, P., Singh, V., Epstein-Ngo, Q., Cunningham, R. M. &amp; Walton, M. A. (2016). Substance use as a risk factor for sleep problems among adolescents presenting to the emergency department. <italic>Journal of Addiction Medicine</italic>, <italic>10</italic>(5), 331. http://doi.org/10.1097/ADM.0000000000000243</mixed-citation>
				<element-citation publication-type="journal">
					<person-group person-group-type="author">
						<name>
							<surname>Zhabenko</surname>
							<given-names>O.</given-names>
						</name>
						<name>
							<surname>Austic</surname>
							<given-names>E.</given-names>
						</name>
						<name>
							<surname>Conroy</surname>
							<given-names>D. A.</given-names>
						</name>
						<name>
							<surname>Ehrlich</surname>
							<given-names>P.</given-names>
						</name>
						<name>
							<surname>Singh</surname>
							<given-names>V.</given-names>
						</name>
						<name>
							<surname>Epstein-Ngo</surname>
							<given-names>Q.</given-names>
						</name>
						<name>
							<surname>Cunningham</surname>
							<given-names>R. M.</given-names>
						</name>
						<name>
							<surname>Walton</surname>
							<given-names>M. A.</given-names>
						</name>
					</person-group>
					<year>2016</year>
					<article-title>Substance use as a risk factor for sleep problems among adolescents presenting to the emergency department</article-title>
					<source>Journal of Addiction Medicine</source>
					<volume>10</volume>
					<issue>5</issue>
					<fpage>331</fpage>
					<lpage>331</lpage>
					<pub-id pub-id-type="doi">10.1097/ADM.0000000000000243</pub-id>
				</element-citation>
			</ref>
		</ref-list>
<fn-group>
		<fn fn-type="other" id="fn1">
			<label>Disponibilidade de dados: </label>
			<p> O conjunto de dados que embasa os resultados deste estudo não está disponível. </p>
		</fn>
		<fn fn-type="other" id="fn2">
			<label>Como citar:</label>
			<p> Sousa, E. A., Freires, L. A., Loureto, G. D. L., &amp; Costa, J. C. A. (2023). Qualidade de sono e sonolência diurna em estudantes universitários: testando um modelo explicativo<italic>. Ciencias Psicológicas</italic>, <italic>17</italic>(2), e-2630. https://doi.org/10.22235/cp.v17i2.2630</p>
		</fn>
		<fn fn-type="other" id="fn3">
			<label>Participação dos autores:</label>
			<p> a) Planejamento e concepção do trabalho; b) Coleta de dados; c) Análise e interpretação de dados; d) Redação do manuscrito; e) Revisão crítica do manuscrito. E. A. S. contribuiu em a, b, c, d, e; L. A. F. em a, b, c, d, e; G. D. L. L. em c, d, e; J. C. A. C. em c, d, e.</p>
		</fn>
		<fn fn-type="other" id="fn4">
			<label>Editora científica responsável:</label>
			<p>Dra. Cecilia Cracco.</p>
		</fn>
</fn-group>
	</back>
	<!--<sub-article article-type="translation" id="s1" xml:lang="en">
		<front-stub>
			<article-categories>
				<subj-group subj-group-type="heading">
					<subject>Original Articles</subject>
				</subj-group>
			</article-categories>
			<title-group>
				<article-title>Sleep quality and daytime sleepiness among college students: testing an explanatory model</article-title>
			</title-group>
			<contrib-group>
				<contrib contrib-type="author">
					<contrib-id contrib-id-type="orcid">0000-0002-7126-5036</contrib-id>
					<name>
						<surname>Andrade de Sousa</surname>
						<given-names>Erlândio</given-names>
					</name>
					<xref ref-type="aff" rid="aff1"><sup>1</sup></xref>
				</contrib>
				<contrib contrib-type="author">
					<contrib-id contrib-id-type="orcid">0000-0001-5149-2648</contrib-id>
					<name>
						<surname>Alves Freires</surname>
						<given-names>Leogildo</given-names>
					</name>
					<xref ref-type="aff" rid="aff2"><sup>2</sup></xref>
				</contrib>
				<contrib contrib-type="author">
					<contrib-id contrib-id-type="orcid">0000-0002-0889-6097</contrib-id>
					<name>
						<surname>Lopes Loureto</surname>
						<given-names>Gleidson Diego</given-names>
					</name>
					<xref ref-type="aff" rid="aff3"><sup>3</sup></xref>
				</contrib>
				<contrib contrib-type="author">
					<contrib-id contrib-id-type="orcid">0000-0002-6730-2156</contrib-id>
					<name>
						<surname>Albuquerque da Costa</surname>
						<given-names>Júlio Cezar</given-names>
					</name>
					<xref ref-type="aff" rid="aff4"><sup>4</sup></xref>
				</contrib>
			</contrib-group>
			<aff id="aff5">
				<label>1</label>
				<institution content-type="original"> Universidade Federal de Roraima, Brazil</institution>
				<institution content-type="normalized">Universidade Federal de Roraima</institution>
				<institution content-type="orgname">Universidade Federal de Roraima</institution>
				<country country="BR">Brazil</country>
			</aff>
			<aff id="aff6">
				<label>2</label>
				<institution content-type="original"> Universidade Federal de Alagoas, Brazil, leogildo.alves.freires@gmail.com</institution>
				<institution content-type="normalized">Universidade Federal de Alagoas</institution>
				<institution content-type="orgname">Universidade Federal de Alagoas</institution>
				<country country="BR">Brazil</country>
				<email>leogildo.alves.freires@gmail.com</email>
			</aff>
			<aff id="aff7">
				<label>3</label>
				<institution content-type="original"> Universidade Federal de Roraima, Brazil</institution>
				<institution content-type="normalized">Universidade Federal de Roraima</institution>
				<institution content-type="orgname">Universidade Federal de Roraima</institution>
				<country country="BR">Brazil</country>
			</aff>
			<aff id="aff8">
				<label>4</label>
				<institution content-type="original"> Universidade Federal de Alagoas, Brazil</institution>
				<institution content-type="normalized">Universidade Federal de Alagoas</institution>
				<institution content-type="orgname">Universidade Federal de Alagoas</institution>
				<country country="BR">Brazil</country>
			</aff>
			<abstract>
				<title>Abstract:</title>
				<p>The current study aimed to test, through structural equation modeling, an explanatory model of the sleep quality and excessive daytime sleepiness among Brazilian college students (<italic>N</italic> = 407). They answered the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), 12-item General Health Questionnaire, Fatigue Assessment Scale (FAS), Academic Stress Scale (ASS), Drug Use Time Questionnaire (DUTQ), and demographic information. The bivariate correlations and multiple regressions provided subsidies for the building of an explanatory model that included psychological discomfort, academic stress and the use of caffeine as explanatory variables for predicting sleep quality, and in turn the latter together with fatigue explaining daytime sleepiness. This model showed acceptable fit. The study concludes that higher levels of academic stress, psychological distress, fatigue and caffeine use are associated with lower sleep quality rates among university students. These findings shed light on the importance of considering both individual and contextual variables to understand the sleep-wake cycle in an academic context. These variables should be considered in further studies that aim to apply and evaluate possible future intervention actions.</p>
			</abstract>
			<kwd-group xml:lang="en">
				<title>Keywords:</title>
				<kwd>sleep quality</kwd>
				<kwd>daytime sleepiness</kwd>
				<kwd>academic stress</kwd>
				<kwd>undergraduate students.</kwd>
			</kwd-group>
		</front-stub>
		<body>
			<p>The act of sleeping is an active, repetitive and reversible behavior that serves a variety of functions, including restorative, physiological and cognitive processes (<xref ref-type="bibr" rid="B1">Ackermann &amp; Rasch, 2014</xref>; <xref ref-type="bibr" rid="B40">Landmann et al., 2014</xref>; <xref ref-type="bibr" rid="B62">Rasch &amp; Born, 2015</xref>). Consequently, sleep is essential for neurogenesis, synaptic plasticity, attention, wakefulness, learning, and memory consolidation (<xref ref-type="bibr" rid="B58">Panjwani et al., 2019</xref>).</p>
			<p>Nevertheless, contemporary society is constantly demanding work, study, and social commitments at irregular hours, resulting in a lack of sleep and harm to physical and mental health (<xref ref-type="bibr" rid="B7">Amaro &amp; Dumith, 2018</xref>). People prefer to sacrifice some sleep time to deal with the various interests they have on a daily basis, assuming that such a practice will not have adverse or harmful consequences (<xref ref-type="bibr" rid="B19">Curcio et al., 2006</xref>).</p>
			<p>Students at universities are a good example of this (<xref ref-type="bibr" rid="B4">Almojali et al., 2017</xref>). It is generally known that they have an irregular sleep pattern, start and end time of sleep, which occurs later on weekends as compared to weekdays, resulting from social and academic demands, adaptation to university settings, and lack of parental supervision (<xref ref-type="bibr" rid="B6">Amaral, 2018</xref>; <xref ref-type="bibr" rid="B9">Araújo et al., 2013</xref>; <xref ref-type="bibr" rid="B60">Phillips et al., 2017</xref>). As an indication of how severe this phenomenon is, such a pattern results in high variation in sleep habits, resulting in a high sleep debt, which is not frequently observed in non-clinical populations or those who do not work shifts (<xref ref-type="bibr" rid="B42">Lemma et al., 2012</xref>; <xref ref-type="bibr" rid="B43">Li et al., 2017</xref>). </p>
			<p>Several factors affect the learning performance of university students, including sleep quality (SQ) and daytime sleepiness (DS) (<xref ref-type="bibr" rid="B35">Huang et al., 2014</xref>). Generally, self-report instruments are used to assess sleep quality based on objective factors (such as nightly awakenings, latency, and sleep duration), as well as subjective factors (such as perception of sleep depth and degree of restoration that individuals feel when they wake up, as well as general satisfaction with sleep; <xref ref-type="bibr" rid="B10">Bertolazi, 2008</xref>). The somnolence is usually an increased propensity to nap/fall asleep during the day or an inability to remain alert during the day (<xref ref-type="bibr" rid="B72">Thorpy &amp; Billiard, 2011</xref>). In addition, it is usually accompanied by low sleep latency, changes in important sleep stages due to accumulated debt, which are common signs that sleep disorders exist (<xref ref-type="bibr" rid="B38">Kaur &amp; Singh, 2017</xref>).</p>
			<p>Since sleep, sleep quality, and sleepiness are related to aspects of physical and mental health as well as cognitive aspects of learning and memory, it is thought that the study of conditions that interfere with these variables is a relevant demand for investigation and intervention by the academic community (<xref ref-type="bibr" rid="B18">Christodoulou et al., 2023</xref>; <xref ref-type="bibr" rid="B22">Fonseca &amp; Genzel, 2020</xref>). In general terms, previous studies have already demonstrated some variables that can predict the quality of sleep and daytime sleepiness in a university population, with emphasis on academic stress (<xref ref-type="bibr" rid="B5">Alotaibi et al., 2020</xref>), psychological distress (<xref ref-type="bibr" rid="B56">Najafi Kalyani et al., 2017</xref>), fatigue (<xref ref-type="bibr" rid="B65">Sajadi et al., 2014</xref>), as well as the use or abuse of psychoactive substances (<xref ref-type="bibr" rid="B81">Zhabenko et al., 2016</xref>).</p>
			<p>With regard to the phenomenon of stress, this is conceived as a state of activation of the organism in response to the perception of a threat, real or imagined, that has the potential to change the organism's condition of subjective well-being and cause feelings of discomfort and/or temporary or permanent discomfort (<xref ref-type="bibr" rid="B41">Lazarus &amp; Folkman, 1984</xref>). Thus, academic stress (AS) is described as an activation reaction to academic stimuli on a physical, emotional, cognitive, and behavioral level (<xref ref-type="bibr" rid="B26">García &amp; Zea, 2011</xref>). Students often perceive taking tests, presenting work in class, being overloaded with assignments, and other situations as stressful (<xref ref-type="bibr" rid="B27">García-Ros et al., 2012</xref>; <xref ref-type="bibr" rid="B45">Lund et al., 2010</xref>). Previous studies have already shown the adverse effects of AS on the SQ of college students in a wide range of situations (<xref ref-type="bibr" rid="B42">Lemma et al., 2012</xref>; <xref ref-type="bibr" rid="B45">Lund et al., 2010</xref>).</p>
			<p>The construct of psychological distress (DP) refers to a group of non-severe, non-psychotic mental disorders that typically involve the presence of anxiety, depression, substance abuse, and low self-efficacy (<xref ref-type="bibr" rid="B49">Massud et al., 2007</xref>), which in turn predicts SQ. In a prospective longitudinal study with Japanese adolescents, <xref ref-type="bibr" rid="B37">Kaneita et al. (2009</xref>) found that sleep disturbance increased the likelihood of becoming mentally ill and vice versa. Another body of research has shown that changes in mental health status are closely related to differences in sleep status (<xref ref-type="bibr" rid="B17">Cheng et al., 2012</xref>; <xref ref-type="bibr" rid="B71">Suzuki et al., 2011</xref>).</p>
			<p>The fatigue variable is typically understood as a state of tension, fatigue, or lack of energy (<xref ref-type="bibr" rid="B25">Fujii et al., 2015</xref>). According to recent research, fatigue may be a symptom brought on by an unhealthy lifestyle (e.g., sedentary behaviors; <xref ref-type="bibr" rid="B76">Wang et al., 2019</xref>), which is a common issue among adults, including university students (<xref ref-type="bibr" rid="B39">Koohsari et al., 2021</xref>). As a result, this variable equally affects the SQ in many groups (<xref ref-type="bibr" rid="B77">Wylie et al., 2022</xref>). It has been demonstrated that there is a strong correlation between normal fatigue and sleep (in a non-clinical population) as well as a relationship between poor sleep quality, short sleep duration, high levels of stress, and a perception of lower levels of subjective health and sleepiness (<xref ref-type="bibr" rid="B2">Åkerstedt et al., 2014</xref>). Another study (<xref ref-type="bibr" rid="B74">Tsai &amp; Lee-Chiong, 2013</xref>) shows the significant prevalence of fatigue among persons with sleep disorders, such as insomnia, obstructive sleep apnea, narcolepsy, etc.</p>
			<p>In addition, substance use/abuse is another important condition since it implies individual physiological and cognitive consequences that, in turn, interact with the sleep-wake cycle (<xref ref-type="bibr" rid="B46">Madras &amp; Kuhar, 2013</xref>). Yet, caffeine has been investigated less frequently (<xref ref-type="bibr" rid="B29">Gillin et al., 2005</xref>). In a meta-analysis, <xref ref-type="bibr" rid="B28">Gardiner et al. (2023</xref>) showed that caffeine usage significantly reduced efficiency, latency, and total sleep duration. Additionally, there is also evidence that students who consume caffeine have poorer sleep quality (<xref ref-type="bibr" rid="B34">Henriques, 2008</xref>). Furthermore, <xref ref-type="bibr" rid="B69">Sin et al. (2009</xref>), in a systematic review, demonstrated that caffeine abstinence promotes an increase in sleep quality.</p>
			<p>Thus, the current study sought to propose an explanatory model in light of the scenario described through Structural Equation Modeling (SEM) of the SQ and DS of a sample of Brazilian university students: the independent variables are PD, AS, fatigue and the use of psychoactive substances; thus, sleep quality and daytime sleepiness are the model's criterion variables. The proposal of a predictive model is a form of obtaining data to be considered in future intervention actions with regard to the health and academic performance of university students; these data, in turn, play a significant role in enhancing student satisfaction with their overall university experience (<xref ref-type="bibr" rid="B44">Lopes et al., 2013</xref>).</p>
			<sec sec-type="materials|methods">
				<title>Materials and Methods</title>
				<sec>
					<title>Participants</title>
					<p>Participants were 407 undergraduate students from a public higher education institution in the North Region of Brazil, located in the city of Boa Vista in the Brazilian State of Roraima. Participants ranged in age from 18 to 63 years (<italic>M</italic>
 <sub>
 <italic>ean</italic>
</sub> = 23 years; <italic>SD</italic>= 6.75). Most of them were female (64.4%), single (82.1%), attending daytime courses (56%), and studying psychology (26.5%). Regarding substance use/abuse: 80.5% of students used caffeine and 51.6% drank alcohol. In addition, the use of other substances was reported: tobacco (7.8%), amphetamines (2.5%), tranquilizers (1.7%), marijuana (7.1%), cocaine (1%), and inhalants (0.2%).</p>
				</sec>
				<sec>
					<title>Measures</title>
					<p>Participants answered an online questionnaire that included questions about age, gender, sexual orientation, marital status, religion, substance use, etc.</p>
					<p><italic>Pittsburg Sleep Scale Index</italic> (PSQI; <xref ref-type="bibr" rid="B15">Buysse et al., 1989</xref>). The PSQI assesses the quality of sleep in the last month. The PSQI version adapted for the Brazilian context (<xref ref-type="bibr" rid="B10">Bertolazi, 2008</xref>) consists of 19 questions, and evaluates seven sleep components: subjective quality of sleep, sleep latency, sleep duration, sleep efficiency, sleep disorders, medication use, and daytime dysfunction. The score can range from 0 (<italic>Very good</italic> / <italic>No problem at all</italic>) to 3 (<italic>Very bad</italic> / <italic>A very big problem</italic>) for each component, with a maximum total score of 21 points. In the current study, the response scale was reversed so that the higher the PSQI score, the better the participants' sleep quality. In this study, according to <xref ref-type="bibr" rid="B48">Marôco and Garcia-Marques (2006</xref>), the Cronbach's alpha of this measure showed moderate reliability (α = .82).</p>
					<p><italic>Epworth Sleepiness Scale</italic> (ESS; <xref ref-type="bibr" rid="B36">Johns, 1991</xref>). The ESS evaluates the respondent's chances of having dozed off or fallen asleep while engaged in eight different activities in daily life (e.g., “Sitting and reading”, “Watching TV”, etc.). The scale items (i.e., eight items) were answered on a four-point scale (ranging from 0 =<italic>would never doze</italic> to 4 =<italic>high chance of dozing</italic>), presenting, in this study, a moderate reliability index, α = .83 (<xref ref-type="bibr" rid="B48">Marôco &amp; Garcia-Marques, 2006</xref>). In the present research, we used the ESS’s Brazilian adaptation (<xref ref-type="bibr" rid="B11">Bertolazi et al., 2009</xref>).</p>
					<p><italic>General Health Questionnaire</italic> (GHS-12; <xref ref-type="bibr" rid="B30">Goldberg, 1972</xref>). The GHS-12 aims to assess the mental health of people through questions that deal with non-psychotic psychiatric symptoms (e.g., “Have you recently lost much sleep over worry?”). The set of items was answered on a four-point Likert scale, with each item ranging from 0 to 3. For negatively worded items, 0 indicated <italic>not at all</italic>, 1 indicated <italic>seldom</italic>, 2 <italic>usual</italic> and 3 <italic>more than usual</italic>, while positively worded items were reversely scored. All items were added to obtain the total score, where higher scores indicate worse mental health. In the current study, the reliability index of the GHS-12 was moderate, α = .80 (<xref ref-type="bibr" rid="B48">Marôco &amp; Garcia-Marques, 2006</xref>).</p>
					<p><italic>Fatigue Assessment Scale (FAS</italic>; <xref ref-type="bibr" rid="B52">Michielsen et. al, 2004</xref>). The FAS consists of 10 items (e.g., “I am bothered by fatigue”; “I get tired very quickly”, etc.). This set of items was answered on a five-point Likert scale (varying from 1 = <italic>never</italic> to 5 = <italic>always</italic>), taking into account how the individual has been feeling in the last few days in relation to fatigue. The reliability index of the FAS, in this study, was moderate, α = .87 (<xref ref-type="bibr" rid="B48">Marôco &amp; Garcia-Marques, 2006</xref>).</p>
					<p><italic>Academic Stress Scale</italic> (ASS). The ASS consists of an adapted version of the Work Stress Scale (WSS; <xref ref-type="bibr" rid="B59">Paschoal &amp; Tamayo, 2004</xref>) and was validated for the university context by <xref ref-type="bibr" rid="B24">Freires et al. (2018</xref>). Its 12 items (e.g., <italic>“</italic>The way tasks are distributed between disciplines has made me nervous”) were answered on a five-point Likert-type scale (ranging from 1 = <italic>strongly disagree</italic> to 5 = <italic>strongly agree</italic>). In the present study, the internal consistency of the ASS was adequate (α = .88).</p>
					<p><italic>Drug Use Time Questionnaire</italic> (DUTQ). This questionnaire consists of 27 items and was used to assess the frequency of use of numerous substances: tobacco, amphetamines, stimulants, tranquilizers, alcohol, marijuana, cocaine, crack, and inhalants. Thus, the DUTQ enabled the identification of occasional and dependent users of some of the most common drugs (<xref ref-type="bibr" rid="B47">Mariño et al., 1998</xref>).</p>
				</sec>
				<sec>
					<title>Procedure</title>
					<p>All the participants were recruited through social networks (e.g., Instagram) and answered an online questionnaire through Lime Survey<italic>.</italic> Each instrument had the necessary instructions to proceed with the answers and was self-administered. Additionally, the collaborating researchers made themselves available through email to address any questions about taking part in the study. Finally, the prerogatives provided for in Resolution No. 510/16 of the Brazilian National Health Council regarding the regulation of research with human beings were respected. The Ethics Committee of a public higher education institution in the North Region of Brazil approved this study (Process No. 726.580, Healthy Sciences Centre).</p>
				</sec>
				<sec>
					<title>Data Analysis</title>
					<p>Statistical analyses were performed using the R language (<xref ref-type="bibr" rid="B61">R Development Core Team, 2015</xref>). Using the Rcommander interface of the Rcmdr package (<xref ref-type="bibr" rid="B23">Fox, 2017</xref>), descriptive statistics were carried out to characterize the sample as well as correlation and linear regression analyses (i.e., associations between antecedent variables and criterion variables: SQ and DS).</p>
					<p>In order to test the explanatory model, the <italic>Lavaan</italic> package was used (<xref ref-type="bibr" rid="B64">Rosseel, 2012</xref>), by applying the Robust Maximum Likelihood (MLR) estimator. For the model fit, we considered the following fit indexes: (a) Chi-square to degrees-of-freedom ratio (S-Bχ2/df), accepting values between 2 and 3, admitting up to 5; (b) Comparative Fit Index (CFI) and Tucker-Lewis index (TLI), which should be greater than .90; (c) Standardized Root Mean Square Residual (SRMR), assuming as recommended a value below .08; and (d) Root Mean Square Error Approximation (RMSEA), with recommended values between .05 and .08, assuming up to .10, where the confidence intervals (90%) do not include a value greater than .10 (<xref ref-type="bibr" rid="B66">Schreiber et al., 2006</xref>). With regard to inferential tests, the direct and indirect effects were based on bootstrapped estimates (10.000 bootstrap simulations; <xref ref-type="bibr" rid="B33">Hayes, 2017</xref>), which are considered significant when the confidence interval (95%) does not include zero.</p>
				</sec>
			</sec>
			<sec sec-type="results">
				<title>Results</title>
				<sec>
					<title>Correlates of sleep quality and daytime sleepiness in college students</title>
					<p>In order to investigate to what extent the independent variables of the present study correlate with the criterion, SQ and DS variables, correlation analyses were performed. With regard to frequency of substance usage, the sample mostly reported the use of caffeine and alcohol; therefore, the other substances were disregarded in the analyses. As can be seen in <xref ref-type="table" rid="t3">Table 1</xref>, DS was negatively related to SQ. In addition, DS was positively correlated with PD, AS, fatigue; the relationship with caffeine use was negative; there was a non-significant relationship with alcohol use. Finally, SQ was negatively correlated with the following variables: PD, AS, fatigue, and caffeine use; again, alcohol use showed a non-significant relationship.</p>
					<p>
						<table-wrap id="t3">
							<label>Table 1:</label>
							<caption>
								<title>Correlates of sleep quality and daytime sleepiness in college students</title>
							</caption>
							<graphic xlink:href="1688-4221-cp-17-02-e2630-gt3.jpg"/>
							<table-wrap-foot>
								<fn id="TFN3">
									<p>* p &lt; .05 ** p &lt; .01</p>
								</fn>
							</table-wrap-foot>
						</table-wrap>
					</p>
				</sec>
				<sec>
					<title>Predictors of sleep quality and daytime sleepiness in college students</title>
					<p>Due to the lack of previous studies that allow consolidating a theoretical elaboration about the SQ in college students, we decided to carry out a multiple linear regression (stepwise method) in order to avoid the multicollinearity effect, aiming to define the significant predictors of the SQ and DS of university students. The antecedent variables were selected, for both criterion variables, based on the significance of their respective correlation coefficients, as well as on the theoretical directionality between them. The results are shown in <xref ref-type="table" rid="t4">Table 2</xref>.</p>
					<p>
						<table-wrap id="t4">
							<label>Table 2:</label>
							<caption>
								<title>Multiple linear regression of sleep quality and daytime sleepiness in college students</title>
							</caption>
							<graphic xlink:href="1688-4221-cp-17-02-e2630-gt4.jpg"/>
							<table-wrap-foot>
								<fn id="TFN4">
									<label>Note:</label>
									<p> B: Unstandardized coefficients; β: Standardized coefficients; <bold>t</bold>: t-statistic; <italic>p</italic>: p-value.</p>
								</fn>
							</table-wrap-foot>
						</table-wrap>
					</p>
					<p>With regard to SQ (<xref ref-type="table" rid="t4">Table 2</xref>), PD, AS, and caffeine use were significant predictors (negative coefficients). Overall, this set of variables (<italic>R</italic> = .55, <italic>F</italic>(3, 404) = 56.94, <italic>p</italic> &lt; .001) explained 31.2% of outcome variability (adjusted R<sup>2</sup>). For the second regression model (i.e., DS as criterion variable), fatigue, positively, and SQ, negatively, were significant predictors. Overall, these variables (R = .43, <italic>F</italic>(2, 406) = 47.25, <italic>p</italic> &lt;.001) explained 19.1% of outcome variability (adjusted R<sup>2</sup>).</p>
				</sec>
				<sec>
					<title>Developing an explanatory model: sleep quality of university students</title>
					<p>The results described above suggest that, among university students, SQ and DS can be understood through the levels of AS, PD, fatigue, and caffeine use, taking into account their explanatory power. Based on these results, we proposed a sequence (i.e., an explanatory model) that combines PD, AS, and caffeine use as predictors of SQ. Furthermore, SQ, along with fatigue, jointly explains the DS. Such analytical scenario corresponded to the elaboration of an explanatory model, tested from the SEM, presented in <xref ref-type="fig" rid="f2">Figure 1</xref>.</p>
					<p>
						<fig id="f2">
							<label>Figure 1:</label>
							<caption>
								<title>Explanatory model of sleep quality of university students</title>
							</caption>
							<alt-text>Note: Standardized coefficients are reported. * <italic>p</italic> &lt; .05 ** <italic>p</italic> &lt; .01.</alt-text>
							<graphic xlink:href="1688-4221-cp-17-02-e2630-gf2.png"/>
						</fig>
					</p>
					<p>With regard to the explanatory model statistical adjustment, results indicated adequate fit as follows: χ²/<italic>df</italic> = 1.14, CFI = .96, TLI = .91, SRMR = .030, and RMSEA = .073 (.031 - .080). Furthermore, the indirect effects were tested. Specifically, PD (β = .09, CI95% = .030 / .082), AS (β = .03, CI95% = .003 / .027), and caffeine use (β = -.03, CI95% = -.498 / -.030) predicted DS through SQ. Finally, the explained variance of the model was determined (<xref ref-type="bibr" rid="B68">Shrout &amp; Bolger, 2002</xref>): the model was able to account for 47% of the variance of SQ and DS of university students.</p>
				</sec>
			</sec>
			<sec sec-type="discussion">
				<title>Discussion</title>
				<p>Until recently, in empirical studies on sleep patterns and DS among university students, researchers tended to focus solely on measuring the levels of these variables, rather than analyzing potential predictors (<xref ref-type="bibr" rid="B35">Huang et al., 2014</xref>; <xref ref-type="bibr" rid="B75">Wang &amp; Bíró, 2021</xref>). Thus, the current study aimed to test an explanatory model of SQ and DS in a sample of Brazilian university students through a structural model. The results indicated that PD, AS and caffeine use negatively impacted SQ. Then, SQ (negatively) and fatigue (positively) explained the DS levels of the sample. The fit of the proposed model was considered adequate (<xref ref-type="bibr" rid="B31">Hair et al., 2014</xref>), reinforcing the findings of previous studies on the relationship between the aforementioned variables (<xref ref-type="bibr" rid="B5">Alotaibi et al., 2020</xref>; <xref ref-type="bibr" rid="B56">Najafi Kalyani et al., 2017</xref>; <xref ref-type="bibr" rid="B65">Sajadi et al., 2014</xref>; <xref ref-type="bibr" rid="B81">Zhabenko et al., 2016</xref>) in a hierarchical manner.</p>
				<p>As expected based on previous research, PD was associated with lower levels of SQ in college students. Indeed, cross-sectional epidemiological studies on adult populations demonstrate that mental health conditions play a central role in SQ (<xref ref-type="bibr" rid="B63">Roberts et al., 2000</xref>). Sleep dysfunction and/or sleep disorders are the most common symptoms observed in clinical populations, and these symptoms are the motivating factor for seeking professional help (<xref ref-type="bibr" rid="B51">Mendlewicz, 2009</xref>). As mentioned, this pattern was also replicated in university students, highlighting that psychological suffering is linked to sleep quality deficits (<xref ref-type="bibr" rid="B76">Wang et al., 2019</xref>). Furthermore, there is evidence that sleep problems and mental health status may have a bidirectional relationship: one may be the cause or result of the other (<xref ref-type="bibr" rid="B54">Morphy et al., 2007</xref>).</p>
				<p>The AS predicted lower levels of SQ among college students, an evidence-replicated finding in the medical-psychological literature (<xref ref-type="bibr" rid="B5">Alotaibi et al., 2020</xref>; <xref ref-type="bibr" rid="B78">Yan et al., 2018</xref>). Students face sleep problems due to their numerous academic tasks and lack of time for rest (<xref ref-type="bibr" rid="B53">Milojevich &amp; Lukowski, 2016</xref>), which is due to pressure for high academic performance (<xref ref-type="bibr" rid="B16">Cardoso et al., 2009</xref>). These findings have a biological correlate. Specifically, there are neural connections and proximity between hypothalamic sleep regulatory centres (suprachiasmatic nucleus) and brain structures involved in stress-related autonomic responses (hypothalamic-pituitary-adrenal axis; <xref ref-type="bibr" rid="B73">Tomfohr et al., 2012</xref>).</p>
				<p>The use of caffeine also had a negative effect on SQ in the structural model tested here. In addition to caffeine's effects on the cardiovascular system, this substance has disruptive effects on sleep, especially when taken in multiple doses throughout the day (<xref ref-type="bibr" rid="B57">Nordt et al., 2012</xref>). In addition, caffeine is used as an &quot;insomnia model&quot;: the metabolic effects of caffeine, which are physiological in nature, are used to develop a physiological arousal model of chronic insomnia in general samples (<xref ref-type="bibr" rid="B12">Bonnet &amp; Arand, 1992</xref>). In terms of physiological correlates, melatonin secretion, the main hormone responsible for sleep synchronization, is controlled by a neurotransmitter affected by caffeine intake (<xref ref-type="bibr" rid="B67">Shilo et al., 2002</xref>), which impacts SQ. </p>
				<p>Finally, as expected, lower levels of SQ predicted a greater likelihood of DS among college students. Since sleep performs functions in the restoration, protection, and conservation of energy, lower levels of sleep quality translate into losses in the functioning of the individual in the short and long term in their physical, occupational, and cognitive functions (<xref ref-type="bibr" rid="B55">Müller &amp; Guimarães, 2007</xref>), which is expressed by daytime sleepiness (i.e., difficulties in maintaining alertness with an adequate level of physiological arousal; <xref ref-type="bibr" rid="B72">Thorpy &amp; Billiard, 2011</xref>). It is worth noting that this condition is generally present in more than half of this population, as reported by studies in Brazil with students of dentistry (<xref ref-type="bibr" rid="B8">Angelin et al., 2020</xref>), medicine (<xref ref-type="bibr" rid="B53">Milojevich &amp; Lukowski, 2016</xref>), and psychology (<xref ref-type="bibr" rid="B20">Danda et al., 2005</xref>). In addition, fatigue positively predicted DS. In fact, in non-clinical populations, higher levels of fatigue are associated with higher levels of workload, represented here by academic tasks (<xref ref-type="bibr" rid="B2">Åkerstedt et al., 2014</xref>), which, in turn, negatively affect the students' routine, influencing the fulfillment of activities and obligations demanded by the academic context (<xref ref-type="bibr" rid="B80">Zakeri et al., 2006</xref>). </p>
				<p>Despite the above findings, the present study is not without limitations. Firstly, since the sample was non-probabilistic, generalization of the results to the Brazilian university population is not allowed. Second, the measures used consisted of self-report instruments. Thus, the effect of social desirability on the participants' responses could not be controlled. Finally, another limitation is related to the research design: a cross-sectional study (<italic>ex-post facto</italic>). In the case of the tested model, although it may be possible to establish a relationship between a set of variables, this does not guarantee the direction (i.e., reverse causality) regarding the influence of a possible third variable (<xref ref-type="bibr" rid="B21">Fife-Schaw, 2010</xref>). </p>
				<p>In summary, the current findings have implications for the development of future interventions for university populations. At the policy-institutional level, educational institutions can focus on building support networks for the student community (<xref ref-type="bibr" rid="B79">Yusuf et al., 2020</xref>), such as customer service, including issues such as resilience training in the face of stressful stimuli (<xref ref-type="bibr" rid="B32">Hasel et al., 2011</xref>) and time management in personal and academic activities (<xref ref-type="bibr" rid="B14">Brus, 2006</xref>), which can create conditions for an adaptive experience in the academic environment. Thus, future studies could either test the predictive effect of other variables on university students' SQ (e.g., anxiety about falling asleep, sleep hygiene practices, etc.), as indicated by <xref ref-type="bibr" rid="B13">Brown et al. (2002</xref>) and <xref ref-type="bibr" rid="B3">Al-Kandari et al. (2017</xref>), or investigate the effectiveness of practical interventions with groups of university students from courses with different areas of concentration (<xref ref-type="bibr" rid="B50">Mendes et al., 2019</xref>), or from different stages of the academic experience (<xref ref-type="bibr" rid="B70">Soares et al., 2014</xref>).</p>
			</sec>
		</body>
		<back>
<fn-group>
			<fn fn-type="other" id="fn1">
				<label>Data availability: </label>
				<p>The dataset supporting the results of this study is not available.</p>
			</fn>
			<fn fn-type="other" id="fn2">
				<label>How to cite:</label>
				<p> Sousa, E. A., Freires, L. A., Loureto, G. D. L., &amp; Costa, J. C. A. (2023). Sleep quality and daytime sleepiness among college students: testing an explanatory model. <italic>Ciencias Psicológicas</italic>, <italic>17</italic>(2), e-2630. https://doi.org/10.22235/cp.v17i2.2630</p>
			</fn>
			<fn fn-type="other" id="fn3">
				<label>Authors’ participation:</label>
				<p> a) Conception and design of the work; b) Data acquisition; c) Analysis and interpretation of data; d) Writing of the manuscript; e) Critical review of the manuscript. E. A. S. has contributed in a, b, c, d, e; L. A. F. in a, b, c, d, e; G. D. L. L. in c, d, e; J. C. A. C. in c, d, e.</p>
			</fn>
			<fn fn-type="other" id="fn4">
				<label>Scientific editor in-charge:</label>
				<p> Dra. Cecilia Cracco.</p>
			</fn>
</fn-group>
		</back>
	</sub-article>-->
</article>