[Towards informed tobacco consumption in Mexico: effect of pictorial warning labels in smokers].

Objective: Evaluate the effect of the first pictorial warning labels on cigarette packs in Mexican smokers.

Materials And Methods: A population-based representative cohort of smokers from seven Mexican cities was surveyed before (2010) and after (2011) the implementation of pictorial warning labels. To determine the change variables representing the cognitive and behavioral impact of pictorial warnings, bivariate and adjusted generalized estimating equations were estimated. Data from the second survey (2011) were analyzed to determine the factors associated with aided recall of specific pictorial warnings, as well as the factors associated with self-report of the impact that these warnings had.

Results: From 2010 to 2011, significant increases were found in smoker's knowledge about smoking risks, the toxic components of tobacco, and the quitline number for receiving cessation assistance. Recall and impact of specific pictorial warnings was generally broad and equally distributed across the smoker population. In comparison with recent ex-smokers interviewed in 2010, more recent ex-smokers in 2011 reported that pack warnings had influenced their decision to quit (RM=2.44, 95% IC 1.27-4.72).

Conclusion: The first pictorial warning labels on cigarette packages in Mexico have had a significant impact on knowledge and behavior.