Do treatment process factors mediate the relationship between type A-type B and outcome in 12-Step oriented substance abuse treatment?

AIMS: One underutilized strategy for enhancing treatment research is to examine intervening factors that link client characteristics to endpoint outcomes. This study tested the hypothesis that Type B substance abusers would demonstrate difficulties engaging in the treatment process, and that these problems would mediate their poorer outcomes. DESIGN: Longitudinal naturalistic study. SETTING: Two intensive 12-Step substance abuse treatment programs. PARTICIPANTS: A sample of 115 men and women seeking treatment. MEASUREMENT: Empirical clustering techniques were used to divide the sample, and the link between type, process factors, and 12-month outcomes was examined. FINDINGS: Hypotheses were not supported. Type Bs did not demonstrate difficulties with the treatment process, but had greater problems sustaining gains posttreatment. Contrary to prediction, Type Bs were better matched to self-help affiliation than Type As. CONCLUSIONS: Findings argue for a more optimistic perspective on treating Type Bs, and for the utility of Type A-Type B in informing treatment research.