Assessing the distinctiveness of psychotherapies and examining change over treatment for anorexia nervosa with cognitive-behavior therapy, interpersonal psychotherapy, and specialist supportive clinical management.

Objective Therapist adherence to cognitive-behavior therapy (CBT), interpersonal psychotherapy (IPT), and specialist supportive clinical management (SSCM) for anorexia nervosa (AN), was examined across three phases of therapy in a randomized clinical trial. Method Adherence in early, middle, and late phase therapy sessions from 53 of 56 participants in the trial was assessed using the CSPRS-AN by independent raters after listening to complete therapy sessions. Results The three forms of psychotherapy were distinguishable by blind raters. Subscale scores were higher for the corresponding therapy than the other therapy modalities. In CBT and SSCM, a phase-by-therapy effect was found, with the CBT subscale highest for CBT, intermediate for SSCM, lowest for IPT, and elevated in the middle phase of CBT and SSCM. The SSCM subscale was highest for SSCM, intermediate for CBT, lowest for IPT, and elevated in the middle phase of SSCM. Adherence to activities around normalizing eating, weight gain, and education about anorexia nervosa was higher in SSCM than in either CBT or IPT. Discussion Ensuring the distinctiveness of therapies in existing clinical trials with differential treatment outcome is essential. Research on adherence to therapy modalities has the potential to help understanding of the effective components of new and existing treatments for AN. © 2016 Wiley Periodicals, Inc. (Int J Eat Disord 2016; 49:958–962).