Within-Person Association Between Daily Screen Use and Sleep in Youth: A Systematic Review and Meta-Analysis.

Abstract

Understanding the within-person association between daily screen use and sleep can help clarify whether this association reflects potentially causal effects or confounding factors. To synthesize evidence on the within-person association between daily screen use and sleep among youth and to examine whether this association varies by screen type, sleep assessment method, or timing of screen use. Ovid MEDLINE, PsycINFO, SPORTDiscus, and Scopus were searched from inception to August 22, 2025, with forward and backward snowball searching. Data were analyzed in October 2025. Studies reporting on children, adolescents, and young adults aged 3 to 25 years that assessed sleep, measured screen time, and examined daily within-person associations between screen time and sleep were analyzed. Random-effects meta-analysis with cluster-robust variance estimation estimated pooled within-person correlations. Subgroup analyses examined moderating effects of screen type, assessment method, and timing. The primary outcome was within-person correlations between screen time and sleep outcomes, including total sleep time, sleep onset, sleep onset latency, sleep efficiency, wake after sleep onset, and subjective sleep quality. A total of 25 studies reporting on 4562 participants were included. A small significant positive within-person correlation was found between screen time and sleep onset (r = 0.079; 95% CI, 0.010-0.149; P = .03), indicating later bedtimes on days with increased screen use. No significant associations were observed for total sleep time, sleep onset latency, sleep efficiency, wake after sleep onset, or subjective sleep quality. Moderator analyses revealed that the association between screen time and subjective sleep quality significantly differed by timing, with screen time after bedtime showing stronger negative correlation (r = -0.092) vs daily (r = -0.026) or evening (r = -0.005) assessments (P = .007). No other significant moderator effects were observed. Per the results of this systematic review and meta-analysis, daily screen time has a small but significant within-person correlation with later sleep onset; however, short-term daily fluctuations in screen time appear to have minimal impact on sleep duration, efficiency, or quality. Screen time may delay bedtime but is not inherently detrimental to other aspects of sleep health in youth, contrasting with between-person studies showing stronger adverse associations.