A systematic review of behavioral experiments vs. exposure alone in the treatment of anxiety disorders: A case of exposure while wearing the emperor's new clothes?

There has been a longstanding debate about whether cognitive techniques in Cognitive Behavior Therapy add to effectiveness of behavioral ones. Cognitive proponents have suggested that behavioral experiments, a cognitive strategy, relative to exposure alone, a behavioral one, are an example of the value of cognitive interventions. Those who have argued that cognitive strategies may not be necessary have also recognized this as a key test. We conducted a systematic review and narrative synthesis of studies that compared these two techniques in the treatment of a range of anxiety difficulties in adults. PyscINFO, MEDLINE and EMBASE were searched from 1957 to 2008, reference lists were examined, and a citation search was conducted. Data were extracted to a standardized coding sheet, and at each stage of selection a proportion of citations were double-coded to establish reliability. 14 studies (total N=644) met inclusion criteria covering obsessive compulsive disorder, panic, social anxiety and specific phobias. Although the methodological limitations of the studies, particularly the use of brief exposure durations and the possibility of therapeutic-allegiance effects, prevent definitive conclusions, there was some evidence that behavioral experiments were more effective than exposure alone.