Background: Norwegian adolescents report very high-perceived morning sleepiness. Delayed sleep phase may be biologically linked to puberty; adolescents sleep less, but may need more sleep than prepubertal children. The study was designed to investigate sleep habits, circadian rhythm and subjective satisfaction with sleep.
Material and methods: Twenty-two high school students, age 17, and parents of 16 primary school pupils, age seven, answered a questionnaire on estimated sleep need, actual time in bed, sleep latency and adequacy of sleep.
Results: The average length of nocturnal sleep in the adolescents was 7.3 hrs on weekdays and 10.1 hrs on weekends. They went later to bed and rose earlier than the children, sleeping 1.7 hrs less before schooldays and 1.6 hrs more during the weekend than the 8.5 hrs which were their own sleep estimate. All the children were reported to satisfy their need for sleep, but none of the adolescents reported feeling content. The larger the difference between hours in bed on weekdays and hours in bed on weekends, the more dissatisfaction was observed.
Interpretation: The present data suggest that the adolescents were chronic partially sleep deprived and had a tendency toward delayed sleep phase. They did not satisfy their need for sleep as defined by themselves, due to late bedtime throughout the week. Also, the late bedtime and late rise time on weekends maintained or furthered the delayed sleep phase.