Effectiveness of behavioural economics-informed interventions to promote physical activity: A systematic review and meta-analysis

Objective: For beneficial health outcomes sufficient and sustained physical activity levels are recommended but difficult to achieve. This systematic review evaluates the effectiveness of behavioural economics (BE)-informed interventions to increase individuals' physical activity level in the long-term. Methods: We conducted a systematic literature search using Medline (via PubMed), PsycInfo, and EconLit (both via EBSCOhost) including randomized controlled trials of at least 24 weeks duration that evaluated BE-informed interventions to promote physical activity in adults. Potential BE approaches were commitment devices, social incentives, motivational feedback, goal setting, gamification, and financial incentives. Risk of bias was assessed using the revised Cochrane risk-of-bias tool for (cluster-) randomized trials. A random-effects meta-analysis was conducted to summarize the outcome measure daily step count. Results: Based on 13 studies with 4347 participants, the BE-informed interventions most often applied were commitment lotteries (n = 8) and social incentives (n = 7). Risk of bias assessment classified five studies as low, six as moderate, and two as high risk of bias. Significant results on study level towards BE-informed interventions were observed for commitment lotteries (n = 3) and gamification (n = 4). Including healthy and diseased individuals in the meta-analysis (n = 10), the increase in daily step count in experimental groups compared to control was statistically significant for the intervention period (standardized mean difference (SMD) = 0.13, 95%-CI: 0.00-0.25, I2 = 59%, p = 0.04) but not for the follow-up (SMD = 0.08, 95%-CI: -0.00-0.17, I2 = 17%, p = 0.06). Excluding high risk of bias studies (n = 2) resulted in statistically significant effects with reduced heterogeneity for both periods. Conclusion: Our review reveals a potential effect of BE-informed interventions to promote physical activity. The small effect underlines the importance to evaluate the behavioural channels which may explain the heterogeneity in individuals' responses to BE strategies.