Process-outcome analysis in computer-aided treatment of obsessive-compulsive disorder

The study purpose was to examine dose-response relationships between behavi or on a computer-delivered treatment program and outcome in obsessive-compu lsive disorder (OCD), and to report the use of human-computer interactions (HCls) as a process measure in psychotherapy research. Thirteen OCD patient s completed three 45-minute sessions at weekly intervals on an interactive computer program which provided vicarious exposure and response prevention for OCD. The scenario modeled exposure to dirt for the treatment of a hand- washing ritual. HCls were recorded and analyzed to provide a detailed descr iption of the behavioral strategies used. The relationship between subject characteristics, process measures, and outcome was examined. Across the thr ee computer treatment sessions, all subjects showed a marked increase in vi carious exposure behavior, that is, enacting a hand-dirtying behavior seque nce on the interactive computer program. Some subjects enacted hand-washing , although this decreased across sessions. A higher amount of vicarious han d-dirtying behavior predicted symptom reduction on the Padua Inventory (PI) . Higher National Adult Reading Test (NART) scores, an intelligence measure , predicted more enactments of hand-dirtying behavior, but the relationship between hand-dirtying and outcome remained significant after controlling f or NART scores. We conclude that HCls are a novel and objective process mea sure that may aid in clarifying specific treatment factors. The relationshi p between hand-dirtying and outcome suggests a likely increased benefit fro m higher treatment dosages. Copyright (C) 2000 by W.B. Saunders Company.