Meta-analyses of randomized controlled trials assessing the effect of digital tools on step count and moderate-to-vigorous physical activity in healthy children and adolescents

Background: Digital tools can influence young people's physical activity both positively and negatively. This meta-analysis (MA) aims to determine whether global interventions based on the use of digital tools are effective in increasing step count and moderate-to-vigorous physical activity (MVPA) among healthy school-aged children.Methods: This MA builds upon a previous umbrella review that identified 43 randomized controlled trials evaluating digital tools aimed at increasing step counts and daily MVPA in healthy children and adolescents aged 6–17 years. Risk of bias was assessed using the revised Cochrane RoB 2 tool. Effect estimates were expressed as weighted mean differences (WMDs) with 95% confidence intervals (CIs). Heterogeneity was assessed using the I² statistic, and τ² (tau-squared) was used to calculate prediction intervals. Sensitivity and subgroup analyses were performed, along with an assessment of small-study effects to detect potential publication bias. This study was registered in PROSPERO (CRD42024510602).Results: Data were extracted from 18 step count and 32 MVPA observations. Although 27.8% of the studies were judged to have a high risk of bias, this did not significantly affect the overall effectiveness of the interventions. The meta-analysis found no significant overall effect of digital interventions on daily step count (WMD: 267.81; 95% CI: −198.58–734.20), but a significant increase in MVPA minutes per day was observed (WMD: 2.72; 95% CI: 0.83–4.61). Subgroup analyses indicated greater effectiveness when the digital component included a wearable device or a combination of tools, a non-digital component was integrated into the intervention design, and the intervention was delivered via a mix of devices.Discussion: Globally, digital interventions appear to be effective in increasing MVPA among school-aged children but not in significantly increasing step counts. The results of the subgroup analyses indicate that the generalizability of digital interventions remains limited. To enhance effectiveness, future interventions should be carefully tailored, taking into consideration specific factors such as the type of digital tool, the delivery device, and the integration of supportive non-digital elements.Systematic Review Registration: PROSPERO CRD42024510602.