Moderators and predictors of treatment outcome for OCD: A comparison of cognitive behavioral therapy Exposure Response Prevention to Acceptance and Commitment Therapy.

AIM: This study examined theory-driven predictors and moderators of treatment outcomes in group-based cognitive behavioral therapy with exposure and response prevention (CBT/ERP) and acceptance and commitment therapy (ACT) for obsessive-compulsive disorder (OCD).

METHOD: A total of 176 adults diagnosed with OCD according to DSM-5 criteria were randomized to either group-based CBT/ERP or ACT. Participants received 14 weekly sessions and were assessed using clinical interviews at baseline, post-treatment, and 6- and 12-month follow-ups.

RESULTS

Anxiety sensitivity, experiential avoidance, and emotion regulation difficulties significantly moderated treatment response, with individuals high on these dimensions benefiting more from CBT/ERP than ACT.

CONCLUSION

These findings were contrary to our hypotheses and underline the importance of investigating the active mechanisms of ACT. Additionally, group therapeutic alliance predicted and moderated treatment outcomes across both interventions.

CLINICAL OR METHODOLOGICAL SIGNIFICANCE OF THIS ARTICLE: This study provides preliminary evidence that anxiety sensitivity, experiential avoidance, and emotion regulation difficulties significantly moderated treatment response, with individuals scoring higher on these dimensions deriving greater benefit from CBT/ERP compared with ACT. These findings were contrary to our hypotheses and underscore the need for further investigation into the mechanisms of action underlying ACT. In addition, group therapeutic alliance moderated outcomes across both interventions.