Associations among Chronotype, Social Jetlag and Academic Performance

Individual circadian rhythms are integral to performance in daily life; particularly in societies dominated by imposed social clocks. Evening types, despite delayed circadian phase are forced to wake early for social obligations, putting them at risk for chronic sleep restriction, and asynchrony in phase of learning. The present study recruited 1800+ university students to complete the Morningness-Eveningness Questionnaire, Munich Chronotype Questionnaire and/or sleep diaries. Evening types showed the highest levels of social jetlag and greatest percentage of sleep lost on work days. Assessments of chronotype by MEQ and MCTQ remained consistent over multiple measurements regardless of keeping a sleep diary; however chronotype assessment did change based on season, with the latest midsleep times occurring in the summer semester. Later midsleep time on free days (MCTQ MSF) was predictive of lower GPA in females; this relationship was not mediated by social jetlag. Considerations regarding measures of chronotype are discussed.