What explains the relationship between the therapist structure × patient reactance interaction and drinking outcome? An examination of potential mediators

Recent research found that among patients in aftercare treatment for alcoholism the level of therapist structure interacted with the level of patients' interpersonal reactance to predict alcohol use outcomes. The present study examined two sets of potential mediators of this interaction effect among a sample from two aftercare sites of Project MATCH (n = 127). The mediator constructs were types of pro-recovery change talk and resistance to therapeutic work. Dependent variables were percentage of days abstinent (PDA) and percentage of heavy drinking days (PHDD) across the year after treatment. Multiple-mediator models using bootstrapped estimates of indirect effects were used to test for mediation. Results indicated that the 'taking steps' aspect of change talk partially mediated the Structure × Reactance interaction effect on both PDA and PHDD post treatment. Resistance was not found to mediate the interaction effect though resistance did predict worse drinking outcomes. Depending on patients' openness to being influenced by others, therapist structure early in treatment may promote or inhibit pro-recovery steps taken by aftercare patients between treatment sessions. Those steps in turn play an important role in predicting future alcohol use.