An Evaluation of the Body Dysmorphic Disorder Symptom Scale as a Measure of Treatment Response and Remission in Psychotherapy and Medication Trials

•The BDD-SS is a broad self-report measure of BDD symptoms and severity.•The BDD-SS demonstrated good psychometric properties in treatment-seeking samples.•It was sensitive to change, but less sensitive than rater-administered BDD-YBOCS.•The BDD-SS can assess symptom change when rater assessments are not feasible. The Body Dysmorphic Disorder Symptom Scale (BDD-SS) is a self-report tool that captures an array of representative behavioral and cognitive symptoms commonly displayed by individuals with BDD. The BDD-SS is regularly used among experts in the field, though its utility as a measure of treatment response has not yet been formally evaluated. Results from two clinical trials of BDD treatment were pooled from an archived database to create a sample of 220 BDD participants who received either psychosocial or medication-based interventions for BDD. We used baseline BDD-SS scores to describe psychometric properties, baseline correlations with other scales to examine the content validity of the BDD-SS, and longitudinal symptom data to evaluate capacity to detect clinically relevant change. Results indicated that the BDD-SS has good psychometric properties and is able to detect symptom change over time, although it showed lower rates of reliable change with treatment relative to the gold standard rater-administered Yale-Brown Obsessive-Compulsive Scale Modified for BDD (BDD-YBOCS). The BDD-SS offers meaningful information about treatment response in a self-report format and may be particularly useful to employ in clinical practice settings as a means of gathering symptom and treatment response data via self-report when rater-administered interviews are not feasible, although it may underestimate the extent of improvement with treatment.