Abstract
BACKGROUND: Childhood obesity and physical inactivity are growing global concerns, particularly in developing countries. Traditional interventions have shown limited success in fostering sustained physical activity (PA) behaviors among children. Serious games and active video games offer an engaging alternative by integrating behavior change techniques within immersive digital environments. This study evaluated the effectiveness of Naji Iriano, a culturally adapted health video game, in improving motivation, self-efficacy, and PA prioritization among children in Bushehr, Iran. METHODS: This randomized clinical trial included 128 primary school students aged 9-12 years, who were allocated to either an intervention group (Naji Iriano) or a control group (no intervention). Assessments were conducted at baseline, 6 weeks post-intervention onset (Post-test-1), and 6 weeks post-intervention completion (Post-test-2). Data collection tools included questionnaires measuring PA motivation, self-efficacy, prioritization, and the Physical Activity Questionnaire for Children (PAQ-C). Data were analyzed using SPSS version 20, employing chi-square tests, independent t-tests, and analysis of covariance (ANCOVA) with a significance level of 0.05. RESULTS: The adjusted ANCOVA analysis showed significant group differences. The intervention group showed significant improvements in PA self-efficacy (p < 0.001), PA prioritization (p < 0.001), and PA levels (p < 0.001) at both Post-test-1 and Post-test-2 compared to the control group. However, no significant changes were observed in body mass index (BMI) between the groups (p = 0.799). Although PA motivation increased at Post-test-1, this effect was not sustained at Post-test-2 after controlling for covariates (p = 0.968). CONCLUSIONS: Health video games such as Naji Iriano can effectively enhance psychological and behavioral determinants of PA in children, providing a scalable, engaging strategy for obesity prevention. Future research should explore long-term adherence, emphasizing the role of parental involvement and environmental support in sustaining behavior change. TRIAL REGISTRATION: This trial was registered in the Iranian Registry of Clinical Trials (IRCT) on 2019-01-02, registration number: IRCT20130317012830N33.