To explore the association between the joint association of screen time on weekdays and weekends with self-rated sleep quality among adolescents, providing scientific basis for improving adolescent sleep health.

Using data from "Huantai Children's Cardiovascular Health Follow-up Cohort" survey conducted during November to December 2023, a total of 1 197 adolescents aged 12-17 years with complete demographic characteristics, physical measurements, and questionnaire data were included. The dose-response relationship between screen time and sleep quality was evaluated by restrictive cubic splines (RCS). Based on screen time on weekdays and weekends (normal: < 2 h/d; excessive: ≥ 2 h/d), adolescents were categorized into 4 groups. Multivariate Logistic regression models were used to analyze the association between the combined effect of screen time on weekdays and weekends and sleep quality.

The RCS analysis results showed that there was a linear dose-response relationship between average daily screen time and poor sleep quality in adolescents (non-linear P>0.05). The results of multiple Logistic regression analysis showed that adjusting for potential covariates, compared with adolescents having normal screen time on both weekdays and weekends, those with excessive screen time on both weekdays and weekends had increased risk of poor sleep quality (OR=2.51, 95%CI=1.33-4.62, P < 0.01). Sex-stratified analysis revealed that girls with excessive screen time on both weekdays and weekends had increased odds of poor sleep quality (OR=3.03, 95%CI=1.23-7.14, P=0.01), compared to girls who had normal screen time on both weekdays and weekends.

A linear dose-response relationship exists between daily screen time and poor sleep quality in adolescents. Excessive screen time on both weekdays and weekends is positively associated with poor sleep quality, particularly more pronounced among female adolescents.