Differential impact of local and federal smoke-free legislation in Mexico: a longitudinal study among adult smokers

objective. to assess the impact of mexico city and federal smoke-free legislation on secondhand tobacco smoke (shs) exposure and support for smoke-free laws. material and methods. pre- and post-law data were analyzed from a cohort of adult smokers who participated in the international tobacco control (itc) policy evaluation suvey in four mexican cities. for each indicator, we estimated prevalence, changes in prevalence, and between-city differences in rates of change. results. self-reported exposure to smoke-free media campaigns generally increased more dramatically in mexico city. support for prohibiting smoking in regulated venues increased overall, but at a greater rate in mexico city than in other cities. in bars and restaurants/cafés, self-reported shs exposure had significantly greater decreases in mexico city than in other cities; however, workplace exposure decreased in tijuana and guadalajara, but not in mexico city or ciudad juárez. conclusions. although federal smoke-free legislation was associated with important changes smoke-free policy impact, the comprehensive smoke-free law in mexico city was generally accompanied by a greater rate of change.