Metacognitive therapy vs. exposure and response prevention for obsessive-compulsive disorder: A randomized clinical trial

Obsessive-compulsive disorder (OCD) is characterized by recurrent obsessions and/or compulsions that cause marked
distress and interfere with daily functioning. Exposure with responsprevention is the current treatment of choice for OCD.
However, ERP for OCD is a good example of the discrepancy between statistically and clinically significant change.
Although several studies and meta-analyses have shown ERP to lead to statistically significant improvements and large
effect sizes, only about 60% of treatment completers achieve recovery. These data show that there is room for
improvement and a need for augmentation of current CBT strategies. It has been suggested that progress might be made
by basing treatments on key cognitive processes involved in the development and maintenance of the disorder, such as
metacognition. So far, two studies have provided support for the efficacy of MCT for OCD.



The present trial is initiated to compare the effectiveness of MCT with ERP, the current treatment of choice for OCD, in an
outpatient clinical sample of patients with OCD. The following hypothesis is formulated: MCT is more effective than ERP,
both statistically significant and clinically relevant.

MCT is more effective than ERP, both statistically significant and clinically relevant.

We will conduct a randomized controlled trial (RCT) with a pretest-posttest-6-month-30-month-follow-up-design.



Estimated time to fill in the questionnaires will take about 360 minutes per participant at max. (4 times 90 minutes)

Participation at the telephonic interview will take 20 minutes per participant at max. (2 times 10 minutes).

Their are no risks for the participants.

Patients will be randomly assigned to
metacognitive therapy or exposure and responsprevention. The interventions will be offered at the Anxiety Disorders Department of PsyQ (Rotterdam and Spijkenisse). Both manual-driven treatments consist of 15 weekly sessions of 45 minutes duration.



Exposure with responsprevention consists of (1) exposure to the anxiety provoking stimuli and (2) prevention of
neutralizing responses that reduce anxiety.

Metacognition refers to knowledge or beliefs about thinking and strategies used to regulate and control thinking
processes.



The metacognitive model of OCD specifies two subcategories of beliefs that are fundamental to the
maintenance of the disorder; (1) metacognitive beliefs about the meaning and consequences of intrusive thoughts and
feelings, and (2) beliefs about the necessity of performing rituals and the negative consequences of failing to do so.

Resulting from the metacognitive model, treatment focuses on modifying patients’ beliefs about thoughts and thought
processes, with the aim to alter the patients’ relationship with their thoughts as opposed to challenging the actual content
of thoughts (as is done in CT).