Abstract:The objective of this systematic review was to examine the relationships between objectively and subjectively measured sleep duration and various health indicators in children and youth aged 5-17 years. Online databases were searched in January 2015 with no date or study design limits. Included studies were peer-reviewed and met the a priori-determined population (apparently healthy children and youth aged 5-17 years), intervention/exposure/comparator (various sleep durations), and outcome (adiposity, emotional regulation, cognition/academic achievement, quality of life/well-being, harms/injuries, and cardiometabolic biomarkers) criteria. Because of high levels of heterogeneity across studies, narrative syntheses were employed. A total of 141 articles (110 unique samples), including 592 215 unique participants from 40 different countries, met inclusion criteria. Overall, longer sleep duration was associated with lower adiposity indicators, better emotional regulation, better academic achievement, and better quality of life/well-being. The evidence was mixed and/or limited for the association between sleep duration and cognition, harms/injuries, and cardiometabolic biomarkers. The quality of evidence ranged from very low to high across study designs and health indicators. In conclusion, we confirmed previous investigations showing that shorter sleep duration is associated with adverse physical and mental health outcomes. However, the available evidence relies heavily on cross-sectional studies using self-reported sleep. To better inform contemporary sleep recommendations, there is a need for sleep restriction/extension interventions that examine the changes in different outcome measures against various amounts of objectively measured sleep to have a better sense of dose-response relationships.Key words: sleep duration, adiposity, body weight, emotional regulation, mental health, cognition, academic achievement, quality of life, well-being, injuries.Résumé : Cette analyse systématique a pour objectif d'examiner la relation entre la mesure objective et subjective de la durée du sommeil et d'autres indicateurs sanitaires chez des enfants et des jeunes âgés de 5 à 17 ans. En janvier 2015, une recherche est faite dans les bases de données en ligne sans contrainte de date et de devis utilisé. Les études retenues sont sanctionnées par des pairs et sont conformes aux critères a priori déterminés : la population (des jeunes apparemment en bonne santé âgés de 5 à 17 ans), l'intervention/exposition/comparaison (durées variées du sommeil) et le résultat (adiposité, contrôle des émotions, cognition/ rendement scolaire, qualité de vie/bien-être, préjudices/blessures et biomarqueurs cardiométaboliques). À cause du haut niveau d'hétérogénéité des études, on utilise des synthèses narratives. Au total, 141 articles (110 échantillons originaux) incluant 592 215 participants distincts de 40 pays différents sont conformes aux critères d'inclusion. Globalement, une plus longue durée de sommeil est associée aux indicateurs de ...