Application of the Stages of Change Scale in a clinical drug trial

The Stages of Change Scale (SOC: McConnaughy, Prochaska, & Velicer, 1983) was used to predict outcome among 131 outpatients with generalized anxiety disorder who were enrolled in a clinical drug trial. As predicted, subjects high on Precontemplation did not experience as much relief from anxiety as subjects low on Precontemplation, whereas subjects high on Contemplation or Action experienced more decrease in anxiety during the trial than subjects low on these stages. Contrary to our hypothesis, only Contemplation was related to illness severity changes, and scores on the Maintenance scale were not related to outcome. Of the four stage scores, only Maintenance was related to premature termination of treatment. There were no differences between drug (adinazolam) and placebo groups and only Action scores interacted with drug/placebo assignment in this study. Results suggest that the SOC may be useful in identifying individuals who are most likely to experience decreased anxiety while enrolled in a clinical drug trial.