Prediction of outcome in the behavioural treatment of panic disorder with agoraphobia.

Outcome was predicted from pre-treatment characteristics for 62 patients with a primary diagnosis of panic disorder with agoraphobia of moderate to severe magnitude who were treated with 16 sessions of behavioural therapy. Two approaches to the task of prediction was compared: (i) predicting class membership as clinically significantly improved at post-test and at 1-year follow-up on a composite score; and (ii) predicting individual change from the same variable. Agoraphobic severity was found to be a significant predictor of clinically significant improvement at both post-treatment and follow-up. It was also found to be a significant predictor of change at post-treatment, but not at follow-up. Instead the duration of the disorder was found to be a significant predictor of change at follow-up. Perceived treatment credibility, motivation, anxious cluster personality disorder or trait anxiety were not identified as significant predictors of outcome.