The treatment of obsessive‐compulsive checking: A randomised trial comparing danger ideation reduction therapy with exposure and response prevention

Abstract

Standard psychological treatment of obsessive‐compulsive disorder (OCD) typically involves the behavioural‐based therapy exposure and response prevention (ERP). This study compared the effectiveness of ERP with the recently developed cognitive therapy‐based treatment package, Danger Ideation Reduction Therapy for obsessive‐compulsive checkers (DIRT‐C) (Vaccaro, Jones, Menzies, and St Clare). Both treatments were delivered in 14 1‐hr individual weekly sessions. Post‐treatment intention‐to‐treat analysis revealed large statistically significant improvements for participants in both ERP (n = 22) and DIRT‐C (n = 28) conditions. However, treatment effect sizes for change in OCD symptom severity at post‐treatment were greater for DIRT‐C than for ERP (3.74 versus 2.89). In addition, at post‐treatment assessment, significantly more participants who received DIRT‐C were recovered compared with those who received ERP (43% versus 14%). Similarly, at 6‐month follow‐up, treatment effect sizes for change in OCD symptom severity were greater for DIRT‐C than for ERP (3.9 versus 2.76). This study provides further evidence of the usefulness of the DIRT‐C package for people with OCD checking subtype. Future research investigating DIRT‐C is warranted.

Abstract

Key words:

• cognitive therapy
• compulsive checking
• danger ideation reduction therapy
• exposure and response prevention
• obsessive‐compulsive disorder

Funding: This study was funded by a National Health and Medical Research Council (NHMRC) project grant and approved by the University of Sydney Human Research and Ethics Committee.

Conflict of interest: None.

Funding: This study was funded by a National Health and Medical Research Council (NHMRC) project grant and approved by the University of Sydney Human Research and Ethics Committee.

Conflict of interest: None.

Notes

Funding: This study was funded by a National Health and Medical Research Council (NHMRC) project grant and approved by the University of Sydney Human Research and Ethics Committee.

Conflict of interest: None.

1. While it is recognised that hoarding may be a disorder separate from OCD, whether compulsive hoarding should be specified as a dimension of OCD or a separate OCD‐related disorder with its own diagnostic criteria is still unclear (see: Mataix‐Cols et al. 2010 for a comprehensive review).

2. Formulae for standardised mean change (g), unbiased standardised mean change (d), and approximate SD of d(s) based on Becker (1988):

g is standardised mean‐change effect size, calculated based on pretreatment SD, g = Mpre − Mpost/Spre;

d is effect size corrected for small sample bias, d = g (1–3/4(n−1) − 1);

SD is approximate standard deviation of d, SD ≈ (2(1 − r_xy))/n + (d2/2n)

Additional information

Funding

National Health and Medical Research Council (NHMRC)