To study the prevalence of reported sleep disturbances and the association between these complaints and psychological status, 529 randomly selected subjects aged 20-45 years were questioned about their sleep symptoms and psychological status by means of questionnaires. In this young population, feeling refreshed in the morning almost every day was reported by only 15.3%. Females reported a significantly longer mean total sleep time (TST) than males (F: 425 +/- 58 minutes, M: 403 +/- 50 minutes; p or = 3/week) (F: 20.1%, M: 10.4%; p