Stress control: A controlled comparative investigation of large group therapy for generalized anxiety disorder: Process of change

One hundred and nine patients with a primary diagnosis of Generalized Anxiety Disorder (GAD) were allocated to either cognitive, behavioural, cognitive-behavioural or placebo versions of Stress Control large group didactic group therapy or to a waiting list condition. In a previous study (White et al., 1992), few differences emerged between the four therapy conditions and all showed significant change when compared to the waiting list. The present study looked at the process of change. Results show evidence of an initial deterioration in cognitive therapy and, when cognitive techniques are taught, deterioration in cognitive-behaviour therapy on some measures. The placebo condition shows marked improvement over the first half of therapy (generally outstripping the other therapies) with this change being whittled away to some degree over the second half of the treatment. There is no evidence suggesting that cognitive therapy/behaviour therapy leads to initial changes in cognitive symptoms/behavioural symptoms. Possible non-specific explanations for these findings are discussed.