Patient Stage of Change predicts outcome in a panic disorder medication trial.

OBJECTIVE: The authors test the hypothesis that patient readiness to change predicts outcome in a placebo-controlled medication trial. METHOD: Out-patients with panic disorder and agoraphobia completed the Stages of Change (SOC) questionnaire, a measure of readiness to change, before being randomly assigned either sustained release (SR) adinazolam or placebo in a 4 week double-blind trial. RESULTS: In the "intent to treat" analysis, for the 202 subjects who made at least one visit after baseline, adinazolam SR was significantly more effective than placebo on most major outcome measures. Of the 126 subjects who completed the SOC questionnaire, regression analyses showed significant correlations between SOC scores and all 5 outcome measures. In a second analysis, cluster membership based on SOC scores was predictive of outcome on 3 of 5 measures. In each statistical analysis, subjects who were not predisposed to change as measured by the SOC were significantly less likely to change. CONCLUSIONS: Patient readiness to change was strongly correlated with outcome in a placebo-controlled panic disorder trial with an effective medication. In this study, the SOC category, Precontemplation (i.e., those subjects who reported the belief that they had no problem) were less likely to change compared to those who believed that they had a problem.