Sleep habits of students attending elementary schools, and junior and senior high schools in Akita prefecture.

It is widely accepted that students in Japan sleep fewer hours than what they actually need. However, epidemiological data on sleep habits among students are scarce. The sleep habits and related problems among 1650 students in Akita prefecture were studied. The results revealed that schoolchildren attending elementary schools seemed to sleep for a sufficient number of hours, whereas students attending junior or senior high schools were not sleeping enough. In particular, approximately half of the students attending senior high schools answered that they slept 6 h or less on weekdays and nodded off during classes more than twice a week.