doi:10.1016/j.brat.2004.11.007
Copyright © 2005 Elsevier Ltd All rights reserved.
How effective are cognitive and behavioral treatments for obsessive–compulsive disorder? A clinical significance analysis
Peter L. Fisher
,
and Adrian Wells
Department of Clinical Psychology, Rawnsley Building, Manchester Royal Infirmary, University of Manchester, Oxford Road, Manchester M13 9WL, UK
Received 22 June 2004;
revised 15 November 2004;
accepted 19 November 2004.
Available online 1 April 2005.
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Abstract
Controlled outcome studies investigating the efficacy of psychological treatments for obsessive–compulsive disorder (OCD) have employed different methods of determining the clinical significance of treatment effects. This makes it difficult to draw conclusions regarding the absolute and relative efficacy of psychological treatments for OCD. To address this issue, standardized Jacobson methodology for defining clinically significant change was applied to recent psychological outcome trials for OCD. The proportion of asymptomatic patients following treatment was also calculated. When recovery is defined by Jacobson methodology, exposure and response prevention (ERP) appears the most effective treatment currently available (50–60% recovered). However, when the asymptomatic criterion is used as the index of outcome, ERP and cognitive therapy have low and equivalent recovery rates (approximately 25%).
Keywords: Obsessive–compulsive disorder; Clinical significance; Efficacy
Table 1.
Characteristics and clinical significance findings of the five outcome studies

AMT, anxiety management training; CBT, cognitive behaviour therapy; ERP, exposure and response prevention.
a Follow-up times vary:
Cottraux et al. (2001)=36 weeks,
McLean et al. (2001)=3 months.
Table 2.
Data used to determine cut off point (a) and the RCI on the Y-BOCS
a Comprises all available pre-treatment scores (
n=300) from the five outcome studies.
b Test–retest reliability over an average of 49 days (
Woody et al., 1995).
Table 3.
Percentage of patients allocated to the Jacobson categories of outcome at post-treatment and follow-up

AMT, anxiety management training; CBT, cognitive behavior therapy; ERP, exposure and response prevention.
*Follow-up times vary: Cottraux et al. (2001)=36 weeks, McLean et al. (2001)=3 months.
Table 4.
Percentage of asymptomatic patients (YBOCS
7) at post-treatment and follow-up by condition for each treatment study

Table 5.
Summary of the percentage of patients allocated to the Jacobson categories of outcome and asymptomatic patients at post-treatment by treatment condition
