Students' chronotype predicts performance in a Brazilian full-time middle school

The performance, whether satisfactory or unsatisfactory, achieved in day-to-day tasks may vary according to several environmental synchronizers, such as 24-hour light-dark cycle. For instance, the human performance on physical and/or cognitive demanding activities achieve its best during day, when body temperature reaches a circadian peak. Moreover, individual differences in the circadian peaks in temperature along with individuals’ timing of sleep is referred to as chronotype. Here, we aimed to answer if in a Brazilian full-time school of early start time (a) the chronotypes affect the students’ performance; (b) there are differences between the students’ performance according to their chronotypes. We expected to find (a) a positive effect of the morning chronotype on the students’ performance, particularly in subjects that take place in early morning; (b) while a negative effect of the evening chronotype in that same period. To address the effect of the chronotype on the students’ scholar performance we build a Generalized Linear Mixed Model (GLMM). Results show that the students’ chronotype affects both their subjective and school-declared performance. In sum, we add evidence for the effect that individual chronotypes have on the students’ performance in a Brazilian full-time middle school. Our results shows that evening-type students are expected to have an increase of 0.038 (p =