The correlation between screen time and obesity in primary school children: A systematic review and meta-analysis of cohort studies

Introduction. Excessive screen time is one of the main causes of a sedentary lifestyle in primary school children. Reduced physical activity and, consequently, decreased energy expenditure can lead to excess fat accumulation in children. The aim of this study is to identify the relationship between screen time and obesity in primary school children. Materials and Methods. The authors conducted a systematic search for information consistent with the study objective in the PubMed, Google Scholar, and Epistemonikos databases, as well as clinical trial registries (ClinicalTrials.gov and ISRCTN: the UK’s Clinical Study Registry). The study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The methodological quality of the included articles was assessed using the ROBINS-E tool. Bias was assessed using the Egger test and a funnel plot. A random-effects model with inverse variance analysis was used for the meta-analysis. Results. The systematic search revealed 12 studies, 5 of which were included in the subsequent meta-analysis. It was found that children who spent more than 2 hours per day in front of a screen had a 1.34-fold higher relative risk (RR = 1.34; 95% CI: 1.18–1.52, p < 0.0001, I² = 28.1%) of overweight/obesity compared to children who spent less than 2 hours per day in front of a screen. The risk of bias of the included publications ranged from ‘low’ to ‘moderate’. No evidence of publication bias was found. Conclusions. The study found that excessive screen time increases the risk of overweight and obesity in primary school children. Systematic review registration: This review is registered in the PROSPERO International Prospective Register of Systematic Reviews (registration number: CRD420251078740).