Psychological Flexibility as Shared Process of Change in Acceptance and Commitment Therapy and Exposure and Response Prevention for Obsessive-Compulsive Disorder: A Single Case Design Study

Changes in psychological flexibility were tracked in a combined protocol of exposure and response prevention (ERP) and acceptance and commitment therapy (ACT) for adults with OCD to assess if changes in psychological flexibility processes were unique to ACT intervention (e.g., not impacted by ERP). Using a nonconcurrent multiple baseline design, four participants received sessions of ERP and ACT while data was collected on psychological flexibility processes of change and OCD symptom severity. Results indicate treatment response for three of four participants based on OCD scores. Contrary to predictions, data suggest both ERP and ACT have positive effects on psychological flexibility. Implications of these findings are discussed in relation to recent research on ACT and ERP for OCD. This study also illustrates a type of research design that can be accomplished in clinical practice.