The purpose of this study was to test the viability of an IRT-derived developmental continuum to describe the severity of alcohol problems in individuals participating in a large treatment matching study (Project MATCH), and to investigate the moderating role of empirical fit to this continuum in the prediction of external validators including treatment outcome. Overall, results were consistent with the first study hypothesis in suggesting that such a continuum could be derived using information from three measures of alcohol use and related problems. Furthermore, there was moderate correspondence between the ordering of severity markers on this continuum and those suggested by Jellinek’s (1946, 1962) in his classic description of the developmental course of alcoholism.
