Personalising circadian hygiene educational initiatives aimed at university students-"He who has ears to hear, let him hear".

The aim of the present study was to characterise "early drop-outs" (n = 3185) out of a group of university students (n = 7766) engaged in an ongoing circadian education initiative, to evaluate its efficacy and direct its developments. The initiative is aimed at improving sleep timing/quality through one of two sets of circadian hygiene advice covering the timing of sleep, meals, exercise and light exposure, and it has already been shown to have a positive effect on sleep timing. This second, interim analysis confirmed the high prevalence of disturbed night sleep and social jetlag amongst students at Padova University. Three-thousand, one-hundred and eighty-five (41.0%) students were early drop-outs. These were more commonly males (46.4 versus 37.6%; χ 2  = 58, p < 0.0001), had later sleep-wake habits, more daytime sleepiness and worse night sleep quality. Chronotype distribution was also different, with a slight but significantly higher proportion of extremely evening/evening types amongst early drop-outs (χ 2  = 10, p < 0.05). These results suggest that the more evening the student, the lower their likelihood of choosing/being able to follow circadian advice.