Our analytical approach relies on differences in policy within birth cohorts, and requires that there are changes in policy over time. Therefore, we limited analyses to the population who approached age of majority during the period in which minimum legal drinking ages were in flux. This population consists of individuals who turned 18 during the years 1967 to 1990, corresponding to birth years 1949 to 1972. We also limited our analyses to records for individuals who could be classified as non-Hispanic White, non-Hispanic Black, or Hispanic of any known or unknown origin. We limited analyses to these large race/ethnicity categories to maximize comparability across death certificate codings from different jurisdictions and different eras. Inclusion of an “other” category would have resulted in a group that was heterogeneous with respect to race and, more problematically, would have changed significantly over time, both as a result of coding changes in the vital statistics system and demographic changes in the United States. We included only records for individuals born in the 50 U.S. states and the District of Columbia in order to facilitate estimation of MLDA exposure. Likewise, we tabulated only deaths occurring in those areas.
