BACKGROUND Chronotype refers to individuals' preference for morning or evening activities. Its two dimensions (morningness and eveningness) are related to a number of academic outcomes. AIMS The main goal of the study was to investigate the incremental validity of chronotype as a predictor of academic achievement after controlling for a number of traditional predictors. In so doing, a further...

Our sleep timing preference, or chronotype, is a manifestation of our internal biological clock. Variation in chronotype has been linked to sleep disorders, cognitive and physical performance, and chronic disease. Here we perform a genome-wide association study of self-reported chronotype within the UK Biobank cohort (n=100,420). We identify 12 new genetic loci that implicate known components o...

background Being a morning or evening type, or ‘chronotype’ might be linked to psychopathology. aims We examined the association between chronotype and depressive and anxiety disorders in a large cohort study, while taking into account relevant sociodemographic, somatic health, and sleep characteristics, as well as type and severity of disorder and the use of psychotropic medication. Method Dat...

The aims of this study were (i) to compare the chronotype distribution of elite athletes to a young adult population and (ii) to determine if there was a tendency for athletes to select and/or participate in sports which suited their chronotype. A total of 114 elite athletes from five sports (cricket, cycling, hockey, soccer and triathlon) participated in this study. The participants' chronotyp...

OBJECTIVE To examine whether chronotype and daily caloric distribution are associated with glycemic control in patients with type 2 diabetes independently of sleep disturbances. RESEARCH DESIGN AND METHODS Patients with type 2 diabetes had a structured interview and completed questionnaires to collect information on diabetes history and habitual sleep duration, quality, and timing. Shift work...

Most recommendations are that adults should obtain 7-8 hours of sleep per night, although there are individual differences in self-reported sleep need. Chronotype (preference for early or late sleep timing), in combination with social demands, may affect the ability to obtain adequate sleep. This questionnaire study assessed perceived sleep need and self-reported sleep timing and duration durin...

This study explores chronotype-dependent tolerance to the demands of working morning, evening, and night shifts in terms of social jet lag, sleep duration, and sleep disturbance. A total of 238 shift-workers were chronotyped with the Munich ChronoType Questionnaire for shift-workers (MCTQ(Shift)), which collects information about shift-dependent sleep duration and sleep timing. Additionally, 94...

Individual differences in circadian phase preference ("chronotype") are linked to sleep schedule variability, psychosocial functioning, and specific properties of the circadian clock. While much is known about the development, distribution, and variability of chronotype in adolescents and adults, assessment in prepubertal children has been hindered by a lack of appropriate, reliable, and valid ...

Chronotype is a construct reflecting individual differences in diurnal preference. Although chronotype has been studied extensively in school-age children, adolescents and adults, data on young children are scarce. This study describes chronotype and its relationship to the timing of the circadian clock and sleep in 48 healthy children aged 30-36 months (33.4 ± 2.1 months; 24 males). Parents co...

Objectives: The aims of this study were to evaluate patterns of circadian preferences and daytime sleepiness, and to examine the extent to which the consumption of stimulant beverages is associated with daytime sleepiness and evening chronotype among Peruvian college-age students. Methods: A total of 2,581 undergraduate students completed a self-administered comprehensive questionnaire that gat...