"Diagnostic shift" from eating disorder not otherwise specified to bulimia nervosa using DSM-5 criteria: a clinical comparison with DSM-IV bulimia.

In the 5th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), the diagnostic threshold for binging and compensation in bulimia nervosa (BN) decreased from twice to once weekly for 3 months. This study investigates the validity of this change by examining whether BN patients and those whose diagnoses "shift" to BN with DSM-5 are similar in their psychological functioning. EDNOS patients whose symptoms met DSM-5 BN criteria (n=25) were compared to DSM-IV BN patients (n=146) on clinically relevant variables. No differences were found on: BMI; weight-based self-evaluation; perfectionism; depression and anxiety symptoms; or readiness for change. Differences were found on one Eating Disorder Inventory subscale (i.e., bulimia), with the BN group reporting higher scores, consistent with group definitions. These findings support the modified criteria, suggesting that psychopathology both directly and indirectly related to eating disorders is comparable between those with once weekly versus more frequent bulimic episodes.