Compare the efficacy of Metacognitive Therapy (MCT), Exposure, and Response Prevention (ERP) for the Treatment of Obsessive Beliefs and Depression Symptoms in Women with Obsessive-Compulsive Disorder (OCD)

Obsessive–compulsive disorder (OCD) is a psychological disorder with debilitating impacts on many aspects of daily functioning, including relationships and quality of life. Exposure to ritual prevention (ERP) is the psychotherapeutic treatment of choice for obsessive–compulsive disorder. Also, metacognitive therapy (MCT), based on Wells’ metacognitive model of OCD aims to modify the maladaptive metacognitive beliefs and processes implicated in the disorder, to alleviate symptoms. The present study aimed to compare the efficacy of Well’s metacognitive therapy (MCT) and exposure and response prevention (ERP) for the treatment of thought fusion symptoms in women with obsessive–compulsive disorder (OCD).

The study was a semi–experimental that was done through a pretest–posttest design using a control group. The statistical population included all OCD patients who referred to the counseling centers in Shiraz city (Fars province, South of Iran) during 2015–2016. A total of 60 patients who had been diagnosed as having OCD by the psychiatrist or clinical psychologist were selected and divided into two groups (each group n=20) (MCT and ERP) and a control group (n=20). Experimental group 1 experienced Wells’ metacognitive therapy in 8 sessions and the experimental group 2, experienced ERP in 14 sessions of 90 minutes during the course of two months. Both experimental and control groups received equal doses of medicine during the course of the study. Participants completed the obsessive beliefs questionnaire and Beck depression instrument as a research scale (Beck, 1996). The participants answered the Beck depressive inventory and obsessive beliefs questionnaire as the study tools. The obsessive–compulsive disorder workgroup designed obsessive beliefs questionnaire. This questionnaire measures three core domains of obsessive beliefs, namely, 1) over the importance and thinking over–control, 2) perfectionism and intolerance of ambiguity, and 3) inflated responsibility and exaggerated danger expectancies. The respondent was asked to declare his/her agreement on each of the options in a scale of 0 to 7. The scale was different agreement, including (–3) strongly disagree, (0) no idea, and (+3) strongly agree. In Iran, Shams et al. (2004) calculated the Cronbach's alpha, split–half estimate, and test–retest of the questionnaire as 0.92, 0.94, and 0.82, respectively. Beck depressive inventory was one of the most widely used questioners and among the oldest tools for measuring the severity of the obsession. It had 21 items and scaled based on a 4–degree range. Its psychometrics features analyzed all over the world (Beck and Steer, 1996). In Iran, Dabson K, Mohammadkhani reported the values of 0.91 and 0.94 for Cronbach’s alpha and the reliability coefficient of this test. The data of the study were analyzed using analysis of covariance via SPSS software package v.21.

The MCT group had a significant reduction (more efficacy) in two factors of thought–action and thought–event fusion in comparison to the ERP group (p<0.001). No significant difference was observed in the thought fusion of the experimental groups. ERP group, on the other hand, showed a significant reduction in all factors in comparison to the control group (p<0.001). 

Despite some methodological limitations, results showed that MCT proved to be a promising psychotherapeutic alternative to the well–established ERP in the treatment of the obsessive–compulsive disorder. Further investigations need to survey the efficacy of MCT to answer questions as to the working mechanisms underlying therapy for obsessive–compulsive disorder.