Sleep habits of Iranian pre-school children in an urban area: Late sleeping and sleep debt in children

Using BEARS (Bedtime problems, Excessive sleepiness, Awakenings during the night, Regularity of sleep, Snoring), and CSHQ (Children's Sleep Habits Questionnaires) screening tools with 224 participants revealed that Iranian children have shorter night sleep duration than expected (9.54 vs 12 h) for their age group. Earlier sleepers had longer night sleep duration (10:36 +/- 1:12; 9:12 +/- 1:06 h, P < 0.001), and total daily sleep time (11:36 +/- 1:42; 10:36 +/- 1:30 h, P= 0.005) than late sleepers. A majority (85%) of nap-takers had sleep bedtime of 22:00 or later. The poor sleep quality of Iranian preschool children is probably due to cultural characteristics, climate differences, or harmful sleep habits.