RESUMO
To analyze individual preference in organizing their behavior within 24 hours[Human chronotypes] also referred to as morningness/ eveningness. Dow Medical College, Dow university of Health Sciences Karachi. From September 2012 to December 2013. Cross-sectional. Subjects [Medical students] from first semester to final semester were invited to participate in this study, A total of 710 subjects were included. Their demographic data such as age, gender was obtained. Instrument is an integrated questionnaire [Horne JA and Ostberg O Morningness- Eveningness questionnaire MEQ original 1976] designed to assess chronotype of young adult population. Out of different existing chronotypes, biggest group which dominated the current study was intermediate type. Present study determined, chronotype of young population [medical students] of this region. The assessment of individual chronotype is important not only for the diagnosis and treatment of sleep disorders, additionally to evaluate ability to adapt for specific work schedule