There was strong evidence that class 3 was the most severe. Compared to the other classes, class 3 endorsed significantly more DSM-IV criteria overall, stronger drinking motives, higher perceived stress, poorer life satisfaction and more behavioral undercontrol/disinhibition. There were, however, some exceptions to this tendency. The two higher severity classes both exhibited elevated levels of endorsement of tolerance and drinking more than intended compared to the lowest severity group. These two classes also did not differ significantly with regard to level of alcohol use. Not unlike the present study, in an LCA of relatives of alcoholic patients from the Collaborative Study on the Genetics of Alcoholism (COGA), classes generally showed a continuum of severity with the exception of withdrawal where the most severe class showed substantial endorsement compared to the other classes (Bucholz et al., 1996).
