Opportunities to distinguish body dysmorphic disorder and social anxiety disorder in clinical practise

Background: Body dysmorphic disorder (BDD) and social anxiety disorder (SA) share some phenomenological similarities (e.g., social fears, depressive symptoms). Up to now, it is unclear which diagnostic instruments are appropriate in clinical practice to distinguish the disorders. Hypotheses: We expect no differences in depressive symptoms, global psychological strain, and self-esteem. Individuals with SA should report a higher level of social anxiety, but a lower level of appearance-related self-relevant attributions. Questionnaires which measure social anxiety and relevance of and investment in appearance should be able to separate the disorders. Methods: Forty-three participants (N=23 with BDD, N=20 with SA) completed the Beck Depression Inventory (BDI), the Brief Symptom Inventory (BSI), the Social Phobia Scale (SPS), the Social Interaction Anxiety Scale (SIAS), the Rosenberg Self-Esteem Scale (RSE), and the Appearance Schemas Inventory-Revised (ASI-R). Moreover, we used the Yale-Brown Obsessive Compulsive Scale (modified for BDD; BDD-YBOCS) as an interview. Results: BDD and SA did not differ significantly in depressive symptoms, global psychological strain, self-esteem, or performance anxiety. Individuals with SA showed higher levels of interaction anxiety than individuals with BDD, whereas for individuals with BDD, self-evaluative and motivational salience of appearance as well as appearance-related obsessive-compulsive symptoms were more pronounced. A decision tree analysis revealed that the BDD-YBOCS could identify 96% of individuals suffering from BDD, and the ASI-R could identify 86 % correctly. Moreover, the SIAS was not suited to differentiate between the disorders. Conclusions: We found specific differences between the two disorders regarding social anxiety and appearance-related standards. High degrees of social interaction anxiety could also be a marker for BDD. For clinical practice, it seems reasonable to screen individuals with high levels of social interaction anxiety for BDD as a matter of routine.