Credibility and Outcome Expectancy in the Unified Protocol: Relationship to Outcomes

Abstract

The credibility of a treatment rationale consists of “how believable, convincing, and logical the treatment is” (Kazdin, 1979, p. 82), while outcome expectancy consists of patients' beliefs about how likely they are to benefit from a treatment. The Unified Protocol for Transdiagnostic Treatment of Emotional Disorders (UP) presents some challenges in this regard since the treatment rationale is not directly tailored to a specific disorder. We sought to examine the treatment credibility of the UP, as well as patients' outcome expectancies regarding this transdiagnostic treatment, and how each of these “common factors” related to outcomes. Results suggest that outcome expectancies were more closely related to outcomes than were ratings of credibility, in line with research on these constructs in other treatments. Ratings of credibility and outcome expectancies for the UP were comparable to previously reported levels of these constructs in other cognitive-behavioral treatments.