The purpose of this paper is to explore the role of binge drinking in forming a second dimension of undergraduate drinkers when considered alongside the DSM-IV criteria. We hypothesized that the existence of a second dimension was due to a subpopulation of college students who drink heavily and experience a lack of control over their drinking. We believed that a data analytic approach to differentiate classes of participants according to their DSM-IV criteria endorsement was an effective way to address this hypothesis. We also thought analyses to identify classes of participants would provide a nice complement to our prior factor analysis, the goal of which was to identify groupings of items. A class of young adult drinkers with difficulty controlling their drinking may have a particularly strong risk profile compared to other classes. To address this possibility, we conducted subsequent analyses to compare classes on measures of alcohol consumption and other indicators of alcohol problem risk (e.g., drinking motives and key personality traits).
