BackgroundThis study aims to assess a tailored community-based intervention protocol for preventing substance use in Iranian adolescents based on social cognitive theory. MethodsAn ecological approach, Mobilizing for Action through Planning and Partnership(MAPP), was used to develop an intervention for preventing substance use among 180 adolescences (14-18 years old) participating in the study in Iran, through six main steps. Outcomes were analyzed 6, 18, and 24 months later by the SPSS.23. RM-ANOVA, ANCOVA, and Pearson correlation tests were used for data analysis.ResultsAlmost more than 40% of the adolescents from Qhahjavarestan county participated in this study in 4 stages measurement. Substance use behavior explainers, including positive outcome expectancies (p<0.001, F=25), negative outcomes expectancies (p<0.001, F=31.2), and self-efficacy (p<0.001, F=12.3), were significantly promoted in the intervention group at three stages (6, 18, and 24 months after intervention). The program demonstrated insignificant reductions in cigarette, alcohol, and drug use at the initial users, but the incidence of new cases of cigarette using (p<0.001, F=9.93) and alcohol drinking (p<0.07, F=2.9) in the intervention group was reduced at 6 and 18 months after the intervention.ConclusionOur results support the effectiveness of a community-based educational program based on social cognitive theory to reduce the incidence of new cases of drug users among adolescents. More effective educational interventions with a greater focus on self-efficacy and social support may be warranted.