Evaluating E-Cigarette Addiction in Thailand: Validation of Dependence Assessment Tools for Policy and Clinical Use

Objective: To adapt and validate the Penn State Electronic Cigarette Dependence Index (PS-ECDI) and the e-cigarette version of the Fagerström Test for Cigarette Dependence (e-FTCD) for use in Thailand and to assess the current status of e-cigarette addiction among Thai users.Material and Methods: A systematic process of translation, cultural adaptation, and pilot testing of the PS-ECDI and e-FTCD was followed. Expert panel reviews, back-translation, and cognitive interviews were conducted to ensure cultural relevance and clarity. The instruments were administered to 193 Thai e-cigarette users. Internal consistency was assessed using Cronbach’s alpha and validity was evaluated through correlation with the Substance Use Disorder Screening Test (SUDST). The current status of e-cigarette addiction was analyzed.Results: The culturally adapted PS-ECDI demonstrated strong internal consistency, with a Cronbach’s alpha of 0.87 and a robust correlation with SUDST. The e-FTCD had a Cronbach’s alpha of 0.57. E-cigarette addiction was highly prevalent in the sample, with 65% of users exhibiting signs of dependence. Younger age, male sex, and concurrent use of other substances were significantly associated with higher levels of e-cigarette addiction.Conclusion: Culturally adapted and validated tools are essential to measure e-cigarette dependence in Thailand. The validated PS-ECDI is a reliable instrument for health professionals and policymakers to assess e-cigarette dependence, facilitating the development of culturally informed public health interventions and regulatory frameworks. Further refinement of the e-FTCD is necessary to enhance its reliability. The high prevalence of e-cigarette addiction among Thai users underscores the need for targeted public health interventions.