The prevalence of students meeting criteria for current alcohol dependence was high, however, this sample excluded lifetime abstainers and was a heavy drinking sample overall (43.8% binge drinking at least once per week), making the high prevalence of alcohol dependence not entirely surprising. It has been suggested recently that the high prevelance of alcohol dependence in college samples might be due to error in the measurement of withdrawal, tolerance and drinking more than intended in young adults who have limited drinking experience (Caetano et al., 2006). Possibly, young adults are confusing the after-effects of intoxication with withdrawal and are mistaking tolerance for how well they maintain control over their drinking while juggling college life (Babor, 2007). In this college sample, class probabilities for withdrawal were low in all three classes (0.10 to 0.30). Tolerance and drinking more than intended were endorsed at high rates in the two groups with high alcohol consumption, but were particularly high in the class 2 “diagnostic orphans” where 81% of those endorsing one criterion endorsed tolerance or drinking more than intended. Of the “diagnostic orphans”
