Measuring the illicit cigarette market in Mexico: a cross validation of two methodologies.

Our results suggest that the optimal practice for the study of illicit trade is to cross validate estimates using both the smoker survey and the littered pack survey. If resources are limited, however, our findings indicate that either method could be used because both yield similar overall results, as longs as the potential biases are considered. Also, consistent with findings from other studies, our results suggest that the tobacco industry exaggerates the scope of illicit cigarette trade.