A randomized controled feasibility trial of metacognitive training with adolescents receiving treatment for anorexia nervosa.

OBJECTIVE: This pilot study investigated the feasibility and preliminary efficacy of the metacognitive training for eating disorders (MCT-ED) program in adolescents with anorexia nervosa (AN). We report attrition and subjective evaluation as well as changes to cognitive flexibility, perfectionism and eating disorder pathology relative to waitlist controls.

METHOD: Female (n = 35, aged 13-17 years) outpatients with a diagnosis of AN (n = 20) or atypical AN (n = 15) completed baseline measures of cognitive flexibility, perfectionism, and eating disorder pathology (May 2020-May 2022). Participants were randomly allocated to either treatment-as-usual (TAU) plus MCT-ED or TAU waitlist condition. All participants completed post-intervention and 3-month follow-up questionnaires.

RESULTS: The MCT-ED condition had a treatment attrition rate <15%. Participants provided positive evaluation of the program. There were large between groups differences favoring MCT-ED at post-intervention and 3-month follow-up for concern over mistakes perfectionism (respective ds = -1.25, 95% CI [-2.06, -.45]; -.83, 95% CI [-1.60, .06]) with a significant group difference post-intervention but not 3-month follow-up.

DISCUSSION: Findings provide tentative support for the feasibility of MCT-ED as an adjunct intervention for young people with AN, however replication is needed with a larger sample size to further explore its efficacy.

PUBLIC SIGNIFICANCE: Metacognitive training for eating disorders (MCT-ED) is a feasible adjunct intervention for adolescents with anorexia nervosa. The intervention, which targets thinking styles and is delivered online by a therapist, received positive feedback, had high treatment retention, and led to reductions in perfectionism by the end of treatment compared to wait-list controls. Although these gains were not sustained long-term, the program is suitable adjunct intervention for young people with eating disorders.