Abstract
INTRODUCTION: In Thailand, school smoke-free policies initially targeted cigarette smoking but now extend to include electronic cigarettes (e-cigarettes). Yet, the impact of this expansion on curbing e-cigarette use in schools is uncertain. This study seeks to explore how e-cigarette control policies and educational initiatives in Thai secondary schools influence students' legal knowledge, perception of harm, current e-cigarette use, and susceptibility to future use. METHODS: This cross-sectional survey was conducted in four regions of Thailand between May and August 2023, involving 6147 students selected through multistage sampling. Data collection utilized a self-reported online questionnaire in Thai, developed using Google Forms. For continuous outcomes, multiple linear regression models assessed relationships between school e-cigarette policy perceptions, covariates, knowledge of e-cigarette laws, and harm perception. Multiple logistic regression models analyzed the association between policy perceptions, covariates, and categorical outcomes: current e-cigarette use and susceptibility. RESULTS: Adjusting for covariates, a positive association was found between students' perceptions of e-cigarette policies and teachings and their knowledge of e-cigarette control laws (B=0.083, p<0.001) and harm perceptions (B=0.491, p<0.001). Additionally, these perceptions were protective against current e-cigarette use (AOR=0.970; 95% CI: 0.95-0.99, p=0.002) and susceptibility among non-users (AOR=0.962; 95% CI: 0.95-0.97; p<0.001). CONCLUSIONS: A heightened perception of e-cigarette policies and teachings in schools is associated with increased legal knowledge, heightened harm perception, and a lower likelihood of current or future e-cigarette use. This underscores the importance of enforcing the e-cigarette-free policy in schools to mitigate vaping susceptibility amid the ongoing youth e-cigarette epidemic.