Treatment expectations, alliance, session positivity, and outcome: an investigation of a three-path mediation model

The aim of this study was to test a 3-path mediation model, in which the effect of treatment expectations on outcome is mediated first by the alliance and then by session positivity.

Archival process and outcome data were used for this investigation. These data had been collected from 116 clients (70% female, 81% White, mean age = 24.1 years), who sought psychotherapy for a variety of reasons at a university-based clinic.

Correlation analyses established that clients' treatment expectations, the therapeutic alliance, session positivity, and outcome were significantly related to each other. A bootstrap (data resampling) procedure was employed to test the hypothesized 3-path mediated effect. The results of this analysis were consistent with the hypothesis that high treatment expectations enhance the therapeutic alliance, which contributes to clients feeling positive at the end of sessions and in turn facilitates improvements in symptoms and functioning.

The current research is the first to provide evidence for this particular model, and thus helps to shed light on the intricacies and underlying dynamics of psychotherapy.