Objective To analyze the effectiveness of school-based tobacco control interventions by comparing students′ knowledge, attitudes, and use of e-cigarettes before and after the implementation of interventions, and to provide a basis for further development of school-based tobacco control measures.

Methods From October 2022 to May 2023, a six-month tobacco control intervention was conducted among all students in a vocational high school in Qingpu district, Shanghai. Anonymous questionnaires were administered before and after the intervention. Propensity score matching was performed using gender, grade, and smoking/vaping status of family members and friends as matching variables. Data were compared using the χ² test.

Results A total of 981 and 819 valid questionnaires were collected at baseline and post-intervention, respectively. After propensity score matching, baseline and follow-up data from 770 students were obtained. At the end of the intervention, 79.5% of the students expressed their hope that the school would continue to promote the construction of a smoke-free environment. After the school-based tobacco control intervention, students′ awareness of the harms of e-cigarettes improved. The proportion of students who agreed that "e-cigarettes pose safety hazards" increased significantly from 81.8% to 85.8% (χ²=4.604, P=0.032). Support for e-cigarette control measures increased among adolescents, especially support for banning e-cigarettes in indoor public places, which increased by 4.4% after the intervention. The proportion of students who had ever tried e-cigarettes increased from 4.4% to 5.5%, while the proportions of current e-cigarette users and those intending to use e-cigarettes decreased.

Conclusions School-based tobacco control interventions are effective in improving students′ knowledge, attitudes, and intentions regarding e-cigarettes, but further efforts are needed to enhance the effectiveness of these interventions.