Multivariate Decomposition Analysis of Factors Influencing Successful Quitting of Smoking in Global Adult Tobacco Survey of India, Waves One and Two

Background Understanding the factors that support sustained smoking cessation is essential for evaluating the effectiveness of tobacco control measures and improving quit outcomes at the population level. This study investigates successful quitting smoking (SQS), defined as abstinence for at least six months, using two waves of the Global Adult Tobacco Survey (GATS), and explores the factors associated with and contributing to changes in SQS over time. Methods We conducted a secondary analysis of GATS India Wave 1 (2009–2010) and Wave 2 (2016–2017). Adults who smoked either currently or in the past 12 months were included, and SQS was assessed among those who reported quitting and remaining abstinent for six months or more. Chi-squares and z-tests were used to examine the difference in characteristics of included participants between two waves and the change in prevalence of SQS among them. Multivariate logistic regression was used to examine associations between SQS and explanatory or tobacco control-related factors within each wave. Multivariate decomposition analysis was conducted to quantify the contribution of each factor to the change in SQS between waves. Results While the prevalence of smoking decreased significantly from 17.18% in Wave 1 to 13.18% in Wave 2, the prevalence of SQS remained unchanged at 0.70%. Higher education and the presence of indoor smoking restrictions at home were consistently associated with greater odds of SQS. Receiving cessation support other than physician advice was associated with higher SQS in Wave 2. However, no significant change in SQS was observed among individuals who received advice from healthcare professionals. The decomposition analysis revealed no statistically significant contribution of individual factors to the overall change in SQS, although smoke-free home rules showed a high positive contribution within the sample. Conclusion The findings suggest that while India has made strong policy gains in reducing smoking, these have not translated into improvements in sustained quitting. Strengthening evidence-based cessation support, particularly beyond routine provider advice, and leveraging digital platforms and household-level interventions could be key to improving SQS rates. Continued monitoring and targeted policies are essential to ensure quit attempts result in lasting success.