Results of this study show promise for a stepped care protocol of EX/RP for OCD, with a response rate of 88% and a 60% reduction in Y-BOCS total score among treatment completers. The response rate in this study was comparable to a previously published study of therapist-directed EX/RP (86%) (Foa, et al., 2005
) as well as the response rate (86%) of the previous stepped care study (Tolin, et al., 2005
). The response rate to Step 1 in this study was similar to the combined response rates of Step 1 (bibliotherapy only) and Step 2 (self-directed EX/RP with minimal therapist contact) in our previous pilot study. Thus, it appears as though combining the first two steps from the pilot study (bibliotherapy with therapist supported EX/RP) produces similar results while reducing the length of time required to achieve symptom improvement for some participants. Further, the cost effectiveness ratio of this trial was superior than that of the pilot study, suggesting that a two step protocol may be financially superior to a three step protocol. Improvements following treatment were also evident in a measure of quality of life with the SDS, suggesting that improvements associated with treatment translated to positive changes in major life functioning areas (work, family, social functioning).
The response rates of this stepped care study, as well as the previously published pilot study were superior to those reported in other studies of minimal therapist EX/RP (Greist, Marks, Baer, Kobak, Wenzel, Hirsch, et al., 2002
; Kenwright, Marks, Graham, Franses, & Mataix-Cols, 2005
; Tolin, et al., 2007
). Unlike other minimal therapist EX/RP studies, participants in this study who did not respond to treatment after Step 1 received therapist directed EX/RP. Thus, the stepped care protocol of this study may account for the superior results compared to other studies that only utilized self-directed or minimal therapist EX/RP.
A stepped care protocol has many advantages that were highlighted in this study. Because the stepped care protocol is self-correcting, each patient only receives the least restrictive and effective amount of treatment. By reducing the burden associated with EX/RP, both financially as well as the time commitment for treatment, a stepped care program may be more acceptable to patients. Furthermore, by reducing the providers’ burden of providing effective treatment (time required to treat each patient), each practitioner trained in EX/RP will be able to see more patients with OCD.
There are limitations to this study and the stepped care method of EX/RP. The small sample size, with only seven treatment completers, significantly limits the generalizability of the results. As this was a small open trial, we cannot compare the effectiveness or cost effectiveness of stepped care treatment to standard EX/RP. Furthermore, a longer follow-up period is needed to evaluate the risk of relapse following stepped care treatment compared to standard EX/RP.
Another limitation of this study is the relatively high attrition rate (50%), which was substantially higher compared to the Foa et al. (2005)
study (28%) as well as the pilot stepped care study (37%). Most participants cited reasons for withdrawing from the study that appeared unrelated to the stepped care protocol. One participant who withdrew during Step 2, however, reported feeling discouraged about not responding to Step 1. It is possible that nonresponse to Step 1 treatment or the delay in receiving Step 2 may increase attrition among those who do not respond to Step 1. Again, a randomized controlled trial comparing attrition rates among those assigned to a stepped care protocol or standard EX/RP is needed to address this issue.
Despite some limitations, stepped care appears to be a promising approach in improving the cost, acceptability, and accessibility of EX/RP for OCD. A significant proportion of patients (36%) responded following Step 1 and did not require more intensive (Step 2) treatment. Identification of pre-treatment factors, such as presence of social anxiety and poorer general mental health, as was identified as indicators for poor response to self-help for panic disorder (Baillie & Rapee, 2004
), can further refine stepped care EX/RP by matching each patient to the least restrictive/costly and effective treatment.