Predictors of treatment outcome : a long-term follow-up study of behavioural treatment for agoraphobia

Abstract

Outcome and predictors of long-term prognosis were investigated in 27 agoraphobic patients who were reassessed 1 to 5 years following exposure-based treatment. The outcome measures used in the original trials were repeated by an assessor who also interviewed the patients. Overall, improvements attained during treatment were maintained at follow-up. Highly significant (p < .0001) improvements were observed on all clinical measures between pretreatment and long-term follow-up. The pattern of improvement was similar to that observed in previous studies: treatment gains were maintained, but patients generally did not display significant continued improvement during the follow-up period. -- Forty-eight percent of follow-up clients achieved the a priori criteria for high endstate functioning. The variables which gave the greatest contribution to the variance in outcome were social phobia, self-efficacy, behavioural avoidance, and later in treatment, agoraphobic severity and cognitive reactivity. Discriminant function analyses of these variables resulted in over 80% correct predictions of outcome group at long-term follow-up. On the other hand, the mode of phobia onset, level of depression, attitude toward treatment, and social support were poor predictors of long-term outcome. Possible reasons for and implications of these findings are discussed.