A randomized controlled trial comparing EMDR and CBT for OCD

 

Marsden, Z., Lovell, K., Blore, D., Ali, S., & Delgadillo, J. (2017). A randomized controlled trial comparing EMDR and CBT for obsessive–compulsive disorder. Clinical Psychology & Psychotherapy, 25(1). https://doi.org/10.1002/cpp.2120

Summary by: Swastika Dutta Gupta

The study by Marsden et al. (2018) investigates and compares the effectiveness of Cognitive Behavioral Therapy (CBT) and Eye Movement Desensitization and Reprocessing (EMDR) in treating Obsessive-Compulsive Disorder (OCD). CBT, especially when using Exposure and Response Prevention (ERP), is widely recognized as the most evidence-based and effective treatment for OCD.

However, the study raises an important question: could EMDR, a therapy primarily used for trauma, offer comparable or complementary benefits for people with OCD—especially those with underlying trauma?

The researchers worked with 55 participants diagnosed with OCD, randomly assigning them to either a CBT group or an EMDR group. Each group received 16 sessions of therapy. For the CBT group, sessions followed the traditional ERP approach, gradually exposing individuals to feared situations while preventing the compulsive responses. The EMDR group followed a standard protocol aimed at processing distressing or traumatic memories that may have contributed to the OCD symptoms.

Results from the study showed that both CBT and EMDR led to improvements in OCD symptoms, as well as reductions in anxiety and depression. However, the CBT group showed significantly greater reductions in OCD symptom severity, as measured by the Yale-Brown Obsessive Compulsive Scale (Y-BOCS), both immediately post-treatment and at follow-up. This reinforced CBT’s position as the most effective standalone therapy for OCD. However, EMDR still showed promise—particularly for individuals whose obsessions and compulsions seemed to be linked to past emotionally charged experiences.

One of the most interesting aspects of the study is the way it challenges a rigid distinction between “trauma therapy” and “OCD therapy.” By suggesting that certain OCD cases may have trauma-related origins, the authors open up a space for more nuanced, individualized treatment planning. They propose that EMDR might be a useful supplementary or alternative method for people who struggle with or don’t fully respond to CBT.

The study also raises questions for future research. For example, how can clinicians best identify whether a person’s OCD has trauma-based origins? Could a combined approach of CBT and EMDR improve outcomes even further? While the sample size was relatively small, the randomized controlled design gives the findings weight and encourages clinicians to consider flexibility in treatment rather than rigid adherence to one approach.

Overall, the study confirms CBT’s superior efficacy for OCD while inviting us to explore EMDR’s role more deeply in complex or comorbid cases.