Association of smartphone use with abnormal social jetlag among adolescents in Korea before and after COVID-19

Is gradual sleep extension effective for social jetlag in adolescents and college students?

“…Nearly half of adolescents have SJL for at least 1 h and more than 15% for 2 h or more [10,11]. In a recent study of Korean adolescents, the prevalence rates of SJL ≥ 2 h was 41.3% [12]. SJL has negative impacts on multiple domains of psychosocial well-being and health, such as sleep disturbances, daytime sleepiness, fatigue, reduced cognitive function, poor academic performance, behavioral and emotional problems, psychiatric disorders, self-harm, metabolic changes, overweight, and risk of cardiovascular diseases [13][14][15].…”