Evaluation of the Effectiveness of a School-Based Smoking Prevention Program Among Young Adolescents in Central Greece

Background: Smoking remains a major global public health challenge. Given that smoking often begins in early adolescence, early preventive programs are essential. This study aimed to measure smoking prevalence, assess knowledge and attitudes toward smoking, and evaluate the impact of a school-based smoking intervention program among students aged 12–13 years in Larissa, Greece. Methods: A total of 769 students participated in the study, yielding an overall response rate of 75.5%. All participants’ knowledge, attitudes, and smoking prevalence were assessed at baseline. The intervention group (n = 316) was then exposed to audiovisual and printed materials, and both intervention and control group participants were followed up at three- and twelve-months post-intervention. Multivariable linear mixed-effects models and generalized estimating equations models were used to evaluate the effects of the intervention. Results: Baseline characteristics of the study participants were balanced between groups. A statistically significant stage × group interaction was observed for both outcomes, indicating improvements in smoking-related knowledge and attitudes (p < 0.001) and a reduction in smoking prevalence (p = 0.026). Conclusions: This school-based intervention effectively improved smoking-related knowledge and attitudes and reduced smoking prevalence among participants. These findings support the integration of early prevention programs into school curricula as a potentially effective approach to improving smoking-related outcomes.