Additional limitations involve the coding of demographic variables. We considered individuals of Hispanic descent to be a separate “racial/ethnic” category, an approach that is consistent with recoding used in recent NSDUH surveys. However, it is possible that some individuals in this group may self-identify as Caucasian or Black rather than Hispanic. In addition, the “Other” category is heterogeneous, and combines various groups that may vary widely in their drinking behavior. Collapsing these categories was necessary due to statistical power considerations. Finally, because of our interest in the college environment, we classified individuals in high-school as “non-(college) students”, when in fact college-bound secondary students may differ considerably from non-college-bound individuals in their drinking behavior.29, 37 It is also important to note that, while it is reasonable to attribute reductions in binge drinking among youth to changes in drinking age laws and related policy initiatives, analyses presented here are intended to document secular trends, but not to assess the direct effects of policy or other variables.
