Integrated School-Based Education for the Control of Overweight and Obesity among Adolescents in Bulukumba, Indonesia: A Quasi-Experimental Study

Background: Overweight and obesity among adolescents are public health problems that may persist into adulthood and increase the risk of non-communicable diseases. School-based health education can support behavioural change; however, the integration of the School Health Unit (UKS) with primary healthcare services has not been optimal. This study evaluated an educational approach integrating researchers, school UKS managers, and UKS programme coordinators at Puskesmas. Methods: This study employed a quasi-experimental design with a pretest-posttest control group approach involving 210 adolescents with overweight or obesity from 21 junior secondary schools within the service areas of 21 Puskesmas in Bulukumba Regency. The participants comprised 105 adolescents in the intervention group and 105 in the control group. The intervention group received integrated education accompanied by an educational module, whereas the control group received the module for self-directed learning. Knowledge was measured using a 20-item questionnaire; physical activity using the Physical Activity Questionnaire for Adolescents (PAQ-A); dietary intake patterns using a Food Frequency Questionnaire (FFQ); self-efficacy using the 10-item General Self-Efficacy Scale (GSES); and anthropometric status using body weight and height. Within-group changes were analysed using the marginal homogeneity, McNemar, and Wilcoxon tests, as appropriate for the type of data. Results: In the intervention group, the proportion with good knowledge increased from 20.00% to 60.00% ( p <0.001), the proportion with high physical activity increased from 0.95% to 20.00% ( p <0.001), and the proportion with high self-efficacy increased from 34.29% to 80.00% ( p <0.001). The proportion in the high dietary intake category decreased from 65.71% to 30.48% ( p <0.001), while mean BMI decreased from 27.14±3.35 to 26.19±3.37 kg/m² ( p <0.001). In the control group, the proportion with good knowledge increased from 27.62% to 55.24% ( p <0.001), the proportion with high self-efficacy increased from 15.24% to 43.81% ( p <0.001), and the proportion in the high dietary intake category decreased from 66.67% to 50.48% ( p =0.001). Physical activity did not change significantly ( p =0.260), while mean BMI changed from 27.05±3.70 to 26.79±3.62 kg/m² ( p =0.104). Conclusions: Integrated school-based education was accompanied by positive changes across several outcomes in the intervention group. The control group, which received the module for self-directed learning, also experienced changes in several outcomes. These findings support the development of school-based educational approaches involving UKS and Puskesmas, with between-group differences interpreted cautiously because the baseline characteristics of the two groups were not fully balanced. Trial registration: Indonesia Clinical Research Registry (INA-CRR), INA-180920261809F4B; retrospectively registered on 18 September 2026.