Therapist adherence to family-based treatment for adolescents with anorexia nervosa: A multi-site exploratory study.

Objective This exploratory study is the first to examine family-based treatment (FBT) adherence and association to treatment outcome in the context of a large-scale, multi-centre study for the treatment of adolescents with anorexia nervosa. Method One hundred and ninety recorded FBT sessions from 68 adolescents with anorexia nervosa and their families were recruited across multiple sites (N = 6). Each site provided 1-4 tapes per family over four treatment time points, and each was independently rated for therapist adherence. Results There were differences in adherence scores within and between sites. ANOVA produced a main effect for site, F(5, 46) = 8.6, p < .001, and phase, F(3, 42) = 12.7, p < .001, with adherence decreasing in later phases. Adherence was not associated to end of treatment percent ideal body weight after controlling for baseline percent ideal body weight (r = .088, p = .48). Conclusions Results suggest that FBT can be delivered with adherence in phase one of treatment. Adherence was not associated with treatment outcome as determined using percent ideal body weight.