Cross-National Variations in Adolescent Sleep Patterns: A Time-Use Study

INTRODUCTION: Adolescents’ poor sleep is a major public health problem that can be influenced by national context. This study adopts a novel 24-hour approach to examine cross-country variations in adolescents’ sleep patterns. METHODS: We use high-quality 24-hour time-diary data from the Multinational Time Use Study (N = 25,248 diaries; mean age 15.4 years; 50.3% girls) across nine countries (i.e., Finland, France, Hungary, Italy, Netherlands, South Africa, South Korea, Spain, and the UK) to examine cross-country variations in adolescents’ sleep duration and timing, including sleep onset (i.e., start of the sleep period) and wake-up time (i.e., end of the sleep period). RESULTS: Results show large cross-national differences in sleep duration on both schooldays (from 7:21 hours in South Korea to 8:51 hours in South Africa) and non-schooldays (from 9:26 hours in South Korea to 10:27 hours in the Netherlands), but also in sleep timing, with earliest sleep onsets and wake-up times in South Africa, and latest sleep onsets and wake-up-times in Spain. The incidence of insufficient sleep duration (i.e., less than 8 hours) on schooldays varies from 19% in South Africa to 68% in South Korea. Participation in four key activities (i.e., eating, screen-based time, socializing, studying) during the two hours prior to adolescent sleep onset differs strongly across countries. Boys sleep slightly longer than girls in most countries, and younger adolescents sleep longer, with some relevant country variations. CONCLUSIONS: Adolescents’ sleep duration and timing, and the nature of activity patterns before sleep onset, differ markedly across national contexts.