The capacity for psychotherapy process scale: development and psychometric validation of patient self-reports.

Objective: Studies were conducted to develop and validate the Capacity for Psychotherapy Process Scale (CFPPS), a self-rating measure of capacity for the psychotherapy process from a trans-theoretical perspective. Method: In Study 1, a two-round Delphi methodology consulting 27 and 15 experts, respectively, was used to select items and identify content validity. In Study 2, 279 clients were recruited for exploratory factor analysis (EFA). In Study 3, confirmatory factor analysis and internal consistency analysis were conducted among 390 outpatients; the discriminant validity and predictive validity were studied in 270 outpatients and 82 psychotherapy outpatients, respectively. Results: The Delphi method resulted in 52 items. Through EFA, the CFPPS was reduced to 20 items, focusing on five factors: motivation, belief, self-revelation, persistence, and insight; the internal consistencies were good (0.92 for total scale and 0.82-0.91 for the factors). The CFPPS was not or was only weakly associated with symptoms. The Bonferroni-corrected partial correlation analyses revealed that the CFPPS was positively related to working alliance and session impact. Conclusions: The CFPPS is a preliminary step toward the self-report assessment of the capacity for psychotherapy process from a trans-theoretical perspective and may potentially be used to predict the working alliance and session impact.