Moderators and predictors of outcome in metacognitive and cognitive behavioural therapy for co-morbid anxiety disorders.

This study aimed to investigate whether two theoretically derived moderators of treatment, degree of worry and avoidance at pretreatment, moderated anxiety from pretreatment to post-treatment in a randomized controlled trial comparing metacognitive therapy and cognitive behavioural therapy. Personality problems, degree of co-morbidity, and demographic characteristics (work status and education) were also investigated. Seventy-four patients with a primary diagnosis of post-traumatic stress disorder, social phobia, or panic disorder with and without agoraphobia were analysed using multilevel modelling. There were no significant predictors of treatment outcome, indicating that the slope was not dependent on worry, avoidance, personality problems, degree of co-morbidity, and demographic characteristics. Furthermore, no interaction with treatment condition was found. Due to the sample size, the results of the moderator analysis should be interpreted with caution and replicated. Worry, avoidance, personality problems, degree of co-morbidity, and demographic variables did not moderate the effect of metacognitive therapy and cognitive behavioural therapy or predict treatment outcome for co-morbid anxiety disorders. Clinical implications are discussed.