Based on model interpretability, information criteria, and the BLRT statistic, the three-class model provided the best fit to the data. The three classes were defined as (1) frequent heavy drinking with high consequences, (2) moderate infrequent drinking with low consequences, and (3) nondrinking with low consequences. These three classes were sufficient to explain the heterogeneity in drinking outcomes at all time points in both outpatient and aftercare samples. Clinically, Class 3 represented those individuals who were not drinking but were experiencing some drinking-related consequences (potentially because of long-standing problems). Individuals expected to be members in Class 2 included those who drank infrequently or lightly. Individuals expected to be in Class 1 displayed heavy, frequent drinking with high drinking-related consequences. The three-class models fit significantly better than two-class models at all time points based on the BLRT, and none of the four-class models fit significantly better than the three-class models (outpatient: posttreatment BLRT = 6.22, p = .31; 6-month BLRT = 5.68, p = .27; 12-month BLRT = 7.77, p = .08; aftercare: posttreatment BLRT = 3.69, p = .67; 6-month
