ABSTRACT
Sleep sufficiency and quality affects medical students' academic learning and understanding. So, this study was conducted to assess sleep quality and its associated factors among medical students. In this descriptive cross-sectional study, 407 medical students [269 interns and 138 externs] were chosen by a multi-stage random sampling method from five hospitals in Tehran, Iran and questioned using Sleep and Day-Time Habits Questionnaire [S and DHQ]. Data were analyzed using descriptive statistic methods and Spearman correlation coefficient test. 407 medical students with mean [ +/- SD] age of 25 +/- 1.67 were studied. 257 [63.1%] and 150 [36.9] were female and male, respectively. 9.1% of students reported their sleep quality as excellent, 36.1% good, 39.3% satisfactory, 13.5% unsatisfactory and 2% poor. There was statistically significant relationship between students' sleep quality and awakening due to environmental noises, day time napping duration, uncommon bed entry time, early morning awakenings, and day time fatigue and drowsiness in class rooms [P<0.001]. This study showed that sleep disorders are prevalent among medical students, intern and extern