Invited Commentary: Use of Epidemiologic Methods to Guide Comprehensive and Equitable Approaches to Policy.

Despite a dramatic reduction in the prevalence of commercial cigarette smoking in the United States, children are still commonly exposed to secondhand smoke (SHS), which is a cause of various pediatric health problems. Further, SHS exposure is patterned by race and class, exacting an inequitable toll on children from families with lesser social and economic advantage. In this issue of the Journal, Titus et al. (Am J Epidemiol. 2023;192(1):25-33) use natural experiment evaluation methods (difference-in-differences) to test whether the recently implemented US Department of Housing and Urban Development policy that forbade smoking in and around New York City Housing Authority buildings affected child respiratory health. The results from their work remind us that policies do not always impact outcomes as we might expect. Given that policy is one of the most potent tools for population health promotion, this work underlines the need for epidemiologists to engage in policy evaluation at all stages of the policy life cycle, in order to discover comprehensive approaches to policy development and implementation that prioritize equity and address structural racism.