A Journey Through Chronotype Changes in University Students

< 0.8), with approximately 70% of students confirming their first assessment at 2 months, with variations (62%-73%) depending on time between assessments and behavioral advice; transitions mostly occurred between adjacent Self-ME categories. Nonetheless, approximately 30% of participants changed category between 2 assessments, and those who moved once were more likely to move again. "Non movers" exhibited more extreme sleep-wake habits. Furthermore, midsleep and social jetlag changed over the calendar year in ways that seemed to reflect the time-course/constraints of the academic year. The 2 circadian hygiene interventions influenced chronotype stability slightly and differently, particularly in morning types, who probably found it easier to comply with the suggestion of advancing sleep-wake timing. In conclusion, chronotype in young adults shows relative stability but is plastic within limits, also in relation to the way it is measured.