An investigator-blinded, randomized study to compare the efficacy of combined CBT for alcohol use disorders and social anxiety disorder versus CBT focused on alcohol alone in adults with comorbid disorders: the Combined Alcohol Social Phobia (CASP) trial protocol

Background: Alcohol use disorders and social anxiety disorder are common and disabling conditions that frequently co-exist. Although there are efficacious treatments for each disorder, only two randomized controlled trials of interventions for these combined problems have been published. We developed a new integrated treatment for comorbid Social Anxiety Disorder and Alcohol Use Disorder based on established Motivational Interviewing (MI) and Cognitive Behaviour Therapy (CBT) interventions for the separate disorders. Compared to established MI/CBT for alcohol use disorders this new intervention is hypothesised to lead to greater reductions in symptoms of social anxiety and alcohol use disorder and to produce greater improvements in quality of life. Higher levels of alcohol dependence will result in relatively poorer outcomes for the new integrated treatment. Methods/design: A randomised controlled trial comparing 9 sessions of individual integrated treatment for alcohol and social phobia with 9 sessions of treatment for alcohol use problems alone is proposed. Randomisation will be stratified for stable antidepressant use. Post treatment clinical assessments of alcohol consumption and diagnostic status at 3 and 6 month follow-up will be blind to allocation. Discussion: The proposed trial addresses a serious gap in treatment evidence and could potentially define the appropriate treatment for a large proportion of adults affected by these problems.