PhD defence K. (Kim) Melchior

The recommended psychological treatment of choice for obsessive-compulsive disorder (OCD) is exposure with response prevention (ERP). Although this treatment is quite effective, recovery rates are modest and drop-out is relatively high. Also, ERP treatment requires amounts of therapist time. A possible way to improve OCD treatment is by taking into account key cognitive processes involved in the development and maintenance of the disorder. The metacognitive model is such an account and pilot findings suggest that the associated metacognitive therapy (MCT) might be an effective treatment for OCD and might be more effective than ERP. In the present manuscript, an outline of the metacognitive model and metacognitive therapy for OCD is given. . It is proposed that two domains of metacognitive beliefs are fundamental in the development and maintenance of OCD: 1) metacognitive beliefs about the significance and consequences of intrusive thoughts, also called fusion beliefs, and 2) beliefs about the necessity of performing ritual behavior. 
According to the metacognitive model, treatment should focus exclusively on modifying patients’ beliefs about the importance and power of intrusive thoughts and the necessity of performing rituals, instead of challenging the actual content of the obsessions and compulsions (Fisher & Wells, 2008).).  Two effectiveness studies were carried out in this manuscript: a pilot study and a randomized controlled trial (RCT) to assess the effectiveness of MCT in comparison to ERP.  We conclude that both MCT and ERP provide positive treatment outcomes in a relatively short time period, which were maintained at six-month follow up. Our results justify the conclusion that MCT is an equally effective therapy next to ERP and can be reliably imbedded for OCD-patients who refuse or drop-out from ERP prematurely or when treatment outcomes with ERP are suboptimal.

The PhD defences will not take place publicly in the usual way. A live stream link has been provided to candidate. The ceremony will begin exactly at 15:30.