Screening for Bipolar Disorder and Finding Borderline Personality Disorder: A Replication and Extension.

The authors' group previously reported that patients who screened positive on the Mood Disorders Questionnaire (MDQ), the most frequently studied screening scale for bipolar disorder, were as likely to be diagnosed with borderline personality disorder (BPD) as with bipolar disorder. A limitation of that study was that the authors examined the performance of the MDQ in patients presenting for various psychiatric disorders, including depression. The recognition of bipolar disorder and its differential diagnosis with BPD is of greatest clinical relevance in depressed patients. In the present report from the Rhode Island Methods to Improve Diagnostic Assessment and Services (MIDAS) project, the authors attempted to replicate their initial findings in a new sample of psychiatric outpatients, and they also examined the performance of the MDQ in depressed patients. The results of the present study were consistent with the original report, thereby indicating that the MDQ is not effective in helping distinguish bipolar disorder from BPD.