Effect of digital health applications with or without gamification on physical activity and cardiometabolic risk factors: a systematic review and meta-analysis of randomized controlled trials.

Background: Use of health applications (apps) to support healthy lifestyles has intensified. Different app features may support effectiveness, including gamification defined as the use of game elements in a non-game situation. Whether health apps with gamification can impact behaviour change and cardiometabolic risk factors remains unknown. We conducted a systematic review and meta-analysis to determine the effect of health apps with gamification compared to non-gamified apps (control) on physical activity and cardiometabolic risk factors. Methods: MEDLINE, EMBASE, and Cochrane library databases were searched through May 21st, 2024. We included controlled trials in adults (≥1 years) of all health backgrounds, with intervention periods ≥8-weeks, assessing the effect of gamification strategies used in health behaviour apps on adherence, cardiometabolic risk factors, total energy, and dietary nutrients of concern. Independent reviewers extracted relevant data and assessed risk of bias. Outcomes included physical activity and cardiometabolic risk factors (adiposity, glycemia, lipids, blood pressure and dietary factors). Data were pooled using the inverse variance method and expressed as mean differences (MD) with 95% confidence intervals (CI). Certainty of evidence was assessed using Grading of Recommendations Assessment, Development, and Evaluation (GRADE). Protocol registration was on ClinicalTrials.gov (NCT04633070). Findings: 36 trials (49 trial comparisons, n = 10,079) met eligibility criteria; most targeted physical activity or weight loss. Use of gamification in apps compared to non-gamified interventions resulted in trivial increases in steps (489 steps/day [64 to 914]; high), and reductions in body mass index (-0.28 kg/m Interpretation: Current evidence provides a good indication that gamification features in apps targeting physical activity or measures of adiposity results in slight improvements in these outcomes compared to non-gamified versions. Recommendations to use an app for increasing physical activity or targeting weight loss should consider those with gamification features. Funding: None.