Metacognitive therapy versus disorder-specific CBT for comorbid anxiety disorders: A randomized controlled trial.

Few studies have compared the effects of Metacognitive therapy (MCT) and Cognitive behavioral therapy (CBT) for comorbid anxiety disorders. In the current study we compared CBT and MCT for heterogeneous anxiety disorders in a residential setting. Ninety patients with a primary diagnosis of Post Traumatic Stress Disorder, Social Phobia or Panic disorder, with and without Agoraphobia, were randomized to either CBT or MCT. Patients were assessed at pre-treatment, post-treatment and one-year follow-up. Primary outcome measures were Beck Anxiety Inventory and ADIS IV and secondary outcome measures were SCID II, Beck Depression Inventory, Penn State Worry Questionnaire, The Symptom Checklist-90 and the Inventory of Interpersonal Problems-64. Treatment fidelity was satisfactory and therapist credibility was equal in both treatments. There was a significant difference in the level of anxiety favouring MCT at post-treatment (d=0.7), but there were no differences at one-year follow-up, mainly due to a further improvement in the CBT group during the follow-up period. Both treatments were efficacious. No differences in effect on comorbid diagnoses and symptoms were found, but MCT produced larger change in personality problems. MCT seems to have a more rapid effect on anxiety symptoms, but there were no significant differences in the long term for patients with comorbid anxiety disorders.