Tobacco control policies predict quit attempts, but household smoking predicts cessation success across 29 countries.

BACKGROUND: Tobacco use remains a global public health challenge, leading to over 8 million annual deaths and significant economic burden. Effective tobacco control and cessation interventions are essential to mitigate these impacts. METHODS: Using data from the Global Adult Tobacco Surveys (between 2011 and 2021) and WHO reports from 29 countries, this study analysed determinants of quitting behaviour among n=51 196 individuals. Random Forest classification models were employed to identify key predictors for two outcomes: quit attempts and successful cessation. The model incorporated individual characteristics and all MPOWER policies, addressing gaps in the existing literature. Permutation variable importance was used to investigate the predictive power of the features. The Random Forest misclassification rates were 6% and 21%, indicating predictive reliability. FINDINGS: Country-level factors, tobacco control legislation and WHO region significantly influence quit attempts. Individual-level factors, specifically smoking habits and smoking-permissive home environments-more strongly predicted successful cessation. INTERPRETATION: Results highlight the importance of comprehensive tobacco control policies in promoting cessation. To improve cessation rates and reduce the global burden of tobacco-related diseases, public health initiatives must enhance the enforcement and reach of tobacco control measures, provide targeted support for people who smoke heavily and people in smoking-permissive environments and integrate a broader range of population-specific influences. Further research is necessary to understand the impact of actual policy enforcement and the cultural dynamics affecting tobacco use and cessation. These findings are crucial for guiding public health policies and interventions aimed at achieving better tobacco cessation outcomes globally.