Kavita Batra (Medicine) co-authored a study, "Global, regional, and national prevalence of second-hand smoke and attributable disease burden in 204 countries and territories, 1990–2023: a systematic analysis for the Global Burden of Disease Study 2023," published in The Lancet Public Health. The first dedicated analysis of second-hand smoke as a global risk factor, it estimates that 2.71 billion people, including 767 million children, were exposed in 2023, accounting for 1.66 million deaths and 44.8 million disability-adjusted life-years. Age-standardized prevalence has dropped 22.2% since 1990, but the number of people exposed has not fallen, and disparities by sex and region persist.