It's the therapist and the treatment: The structure of common therapeutic relationship factors.

Objective: Prior research has established that common therapeutic relationship factors are potent predictors of change in psychotherapy, but such factors are typically studied one at a time and their underlying structure when studied simultaneously is not clear. We assembled empirically validated relationship factors (e.g., therapist empathy; patient expectations; agreement about goals) into a single instrument and subjected it to factor analysis. Method: The instrument was applied to patients (N = 332) undergoing intensive psychotherapy of different types for depressive disorders, anxiety disorders, eating disorders, and childhood trauma in an inpatient specialized mental health setting. In order to examine the psychometric properties of the scale, we used half the sample (N=164) to conduct exploratory factor analysis (EFA) and parallel analysis before we tested the solution using exploratory structural equation modeling (ESEM) on the second half of the sample (N=168). Measurement invariance analysis was conducted to examine the stability of the factor structure. Results: The analysis yielded two factors, which were termed 1. "Confidence in the therapist" and 2. "Confidence in the treatment." Discussion: When assessed simultaneously, patients differentiate between their evaluation of the therapist and of the treatment. The results indicate that there is substantial overlap among previously established relationship factors.Trial registration: ClinicalTrials.gov identifier: NCT03503981.