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Date of Award


Degree Type

Dissertation (On-Campus Access Only)

Degree Name

Doctor of Psychology (PsyD)

Committee Chair

Paula Truax, PhD

Second Advisor

Jay C. Thomas, PhD, ABPP


A meta-analysis was conducted to evaluate the comparative effectiveness of exposure and response prevention (ERP), cognitive therapy (CT), and cognitive-behavioral therapy (CBT) in the treatment of obsessive-compulsive disorder (OCD). Many studies describe these methodologies individually, but few trials have been conducted that consider the quality of the treatment methods used. Much recent energy has been devoted to forwarding a newer, more specific CT version; this trend has occurred in the absence of adequate comparisons with gold-standard ERP, sparking the need for the current comparison. Besides considering the general effectiveness of these three methods, additional questions were investigated to better understand what kinds of methodologies should be considered in comparisons in order to fully appreciate their performance. Questions of cost-effectiveness about the various approaches were also explored, looking first at patient cost-effectiveness, and secondly at provider cost effectiveness. Lastly, it was examined whether ERP and CT differentially impacted obsessions or compulsions. A total of 25 trials from 20 studies were included. Contrary to studies that champion the newer CT, this study suggested that gold standard ERP still outperforms the higher-specificity CT. Several aspects were observed to produce optimal outcomes, regardless of treatment methodology chosen, namely: (1) therapist-controlled treatment, (2) treatment duration, (3) treatment frequency, and (4) individual format. Given these findings, comparisons of these methodologies should not be conducted unless the optimizing variables are adhered to across comparisons, as doing so would produce more meaningful comparative findings. Whether considering cost-effectiveness for the patient or the provider, the gold-standard application of ERP was most effective. This advantage was slight, however; as patient-groups are known to exist that do not respond well to ERP, this makes CT possibly an important alternative. Lastly, there was no differential impact detected on obsessions or compulsions based on treatment mode. Overall, these findings are discussed in terms of how to best conduct future studies in order to enhance usefulness and accuracy, especially in comparative analyses of behavioral and cognitive interventions.