Detecting psychotic major depression using psychiatric rating scales

Objective: The aim of this study was to assess whether individual or clusters of psychiatric symptoms can differentiate patients with psychotic major depression (PMD) from those with nonpsychotic depression (NPMD). Method: Data were pooled from two studies investigating patients with moderate depression. A total of 129 subjects were studied. Patients in Sample 1 were unmedicated, while the majority of the patients in Sample 2 were taking psychotropic medications. Baseline rating scales were obtained for all subjects, including the Hamilton depression rating scale and the brief psychiatric rating scale (BPRS). We used discriminant function analyses, logistic regression, and ROC analyses to determine the patterns in symptoms that differentiated the groups. Results: Psychotic patients were adequately differentiated by the unusual thought content (UTC) item of the BPRS. Even mild UTC endorsement was an indicator of PMD. Furthermore, results suggest that the positive symptom subscale of the BPRS was even better at differentiating PMD from NMPD patients. Sensitivity and specificity for this scale were 84% and 99%, respectively. Conclusion: Psychotic major depression is often undiagnosed and poorly treated. One reason for this trend is the failure of physicians to inquire in a more detailed manner about positive symptoms in patients with primary mood symptoms. Although physicians are not likely to have the time to conduct an entire BPRS during an evaluation, our results suggest that a few key symptoms, if assessed directly, may aid the psychiatrist to more effectively diagnose and subsequently treat their depressed patients. (c) 2005 Elsevier Ltd. All rights reserved.