Effects of reducing screen media use on mental health, sleep, physical activity, heart rate variability, and...

Digital media has become deeply embedded in the daily lives of young people, raising concerns about potential effects on mental health, sleep, and physical activity. Although observational studies suggest associations between extensive screen media use and adverse health outcomes, causal evidence remains limited due to confounding and reliance on self-reported measures. Most experimental studies have also focused on individual-level interventions and adult populations. In addition, little is known about how screen media use may influence social dynamics among peers. The PeerScreen trial aims to investigate the effects of reducing screen media use on mental health, sleep, physical activity, heart rate variability, and behavioral patterns among adolescents and young adults within naturally occurring peer groups.

The PeerScreen trial is a parallel-group cluster-randomized controlled trial in which peer groups of adolescents and young adults aged 13-24 years are randomized to either a four-week screen media reduction intervention or a control condition. Participants in the intervention group will be instructed to reduce smartphone use to one hour per day and television, computer, and tablet use to 14 h per week, and leave screen media devices outside the bedroom. We plan to recruit 80 peer groups including 2-6 peers. Data collection combines questionnaires on mental health and well-being, daily reports of mood, sleepiness, and social interactions, and objective monitoring of screen media use, sleep, physical activity, and heart rate variability using a custom application and a wearable device. Bluetooth beacon data will be used to objectively assess social interactions and geolocation data will be used to add context to the observed interactions.

This study will provide detailed experimental evidence on the effects of reducing screen media use among young people in a real-world peer context and may advance understanding of both individual and social mechanisms linking screen media use to well-being and behavioral measures.

ClinicalTrials.gov: NCT07531290 Date of registration: 2026-04-15.