Group schema therapy versus group cognitive behavioral therapy for patients with social anxiety disorder and comorbid avoidant personality disorder: a randomized controlled trial

Background Patients with social anxiety (SAD) and comorbid avoidant personality disorder (AVPD) are severely impaired. Group cognitive behavioral therapy (GCBT) is considered an effective treatment for SAD. More knowledge on treatment of SAD with comorbid AVPD is needed. Schema therapy, developed for personality and chronic mental disorders, may be a promising treatment. Methods We conducted a randomized controlled trial in an outpatient population (n=154) with both SAD and AVPD. Group Schema Therapy (GST) and GCBT were compared on SAD symptoms (Liebowitz Social Anxiety Scale) and manifestations of AVPD (Avoidant Personality Disorder Severity Index). Results Intention-to-treat analysis showed no significant differences between treatments at 3 months post-treatment and one-year follow-up. Both modalities led to significant and substantial improvements. No significant between-differences were found in depressive symptoms (Inventory of Depressive Symptoms) and quality of life (World Health Organization Quality of Life-BREF). Per-protocol analysis showed similar outcomes and no significant differences in recovery from SAD and AVPD. Significantly more patients completed GST. Conclusion GST and GCBT are valuable treatments for SAD with comorbid AVPD. The higher treatment retention in ST indicates ST is more acceptable than GCBT. Future studies should focus on enhancing treatment effects and improving retention to GCBT.