Processes of symptom change in psychotherapy: Investigating the role of therapist adherence, competence and the therapeutic alliance

A growing body of research supports the claim that a variety of psychotherapies are efficacious in the treatment of mental disorders. However, the mechanisms through which these therapeutic modalities result in symptom alleviation are not yet clear. In this dissertation, three process-outcome investigations were conducted to elucidate the relationship between therapist adherence/competence, the therapeutic alliance, patient skills, and treatment outcome. In the first study, I conducted a meta-analytic review of studies in which therapist adherence or competence was examined in relation to outcome. Surprisingly, neither the mean adherence-outcome (r = .02) nor competence-outcome (r = .07) effect size estimates were found to be significantly different from zero. Moderator analyses revealed that larger competence-outcome effect size estimates were associated with studies that either targeted depression or did not control for the influence of the therapeutic alliance. In the second study, I examined the relations of two factor-analytically derived components of the Working Alliance Inventory (WAI) with depressive symptom change that occurred either prior to, or subsequent to, an early and late session of cognitive therapy (CT). Variation in symptom change subsequent to the early session was significantly related to the WAI factor that assesses therapist-patient agreement on the goals and tasks of therapy, but not to a factor assessing the affective bond between therapist and patient. In contrast, both factors, when assessed in a late session, were significantly predicted by prior symptom change. In the third study, measures of therapist adherence and the therapeutic alliance were examined simultaneously in the context of CT for depression in predicting depressive symptom change and patient use of CT skills. Results indicated a differential pattern of prediction in the two samples examined. In one, CT techniques exhibited a stronger association with patient CT skills and symptom change relative to the alliance, whereas the reverse pattern emerged in the second sample. A baseline symptom severity X CT techniques interaction indicated that between-study differences in intake depression severity might in part explain the process-outcome differences. These findings suggest that the nature of the therapy sample examined may influence process-outcome findings in psychotherapy research