Brief report: sudden gains in cognitive-behavioral group therapy and group psychotherapy for social anxiety disorder among college students.

The present study examined sudden gains (SGs; large symptom improvements between adjacent treatment sessions) and its association with treatment outcome in a randomized-controlled trial comparing cognitive-behavioral group therapy (CBGT) versus group psychotherapy (GPT; designed to incorporate only non-specific factors) for social anxiety disorder (SAD). SAD symptoms were assessed after each treatment session in a sample of 45 college students. Independent assessors evaluated symptom severity at baseline, post-treatment and follow-up. A total of 10 (22.2%) participants experienced SGs during treatment. No differences were found in symptom improvement at post-treatment or follow-up between individuals with and without SGs. SGs appeared at similar rates across both treatments but were associated with greater improvements at post-treatment and follow-up in GPT compared to CBGT. Majority of SGs in CBGT occurred early in treatment before the provision of specific treatment techniques. These results suggest that non-specific treatment factors may be important in promoting SGs.