Distribution of chronotypes in a large sample of young adult Saudis.

Background And Objectives: There are no published data on the chronotypes of young Saudi adults. This study assessed the distribution of chronotypes in college-aged Saudis.

Design And Setting: Cross-sectional survey of college students.

Patients And Methods: A validated abridged version of the original Horne and Ostberg morningness-eveningness questionnaire (MEQr) was used to assess the chronotype of 759 subjects.

Results: Of 540 (71.1%) males and 219 (28.9%) females participated in this study ( age range, 18-32 years), 138 (18.2%) were "morning-types," 417 (54.9%) were "neither-types" and 204 (26.9%) were "evening-types." There was no significant gender difference in MEQr typology. In Saudis, particularly males, the frequency of morning typology was somewhat higher than that reported for individuals in similar age groups in some Western countries.

Conclusion: Most Saudi college students had no preference for morningness or eveningness and were classified as "intermediate-types." Morningness appears to be slightly more common in Saudis, especially males, than in individuals of some Western societies.