Evaluating Depressive Symptoms in Schizophrenia: A Psychometric Comparison of the Calgary Depression Scale for Schizophrenia and the Hamilton Depression Rating ScaleSchennach R. · Obermeier M. · Seemüller F. · Jäger M. · Schmauss M. · Laux G. · Pfeiffer H. · Naber D. · Schmidt L.G. · Gaebel W. · Klosterkötter J. · Heuser I. · Maier W. · Lemke M.R. · Rüther E. · Klingberg S. · Gastpar M. · Riedel M. · Möller H.-J.
aDepartment of Psychiatry and Psychotherapy, Ludwig-Maximilians-University, Munich, bPsychiatric Clinic, District Hospital, Augsburg, cPsychiatric Clinic, Inn-Salzach Hospital, Wasserburg/Inn, dPsychiatric Clinic, Isar-Amper Hospital, Munich-Haar, eDepartment of Psychiatry and Psychotherapy, University of Hamburg, Hamburg, fDepartment of Psychiatry and Psychotherapy, University of Mainz, Mainz, gDepartment of Psychiatry and Psychotherapy, Medical Faculty, Heinrich-Heine-University, Düsseldorf, hDepartment of Psychiatry and Psychotherapy, University of Cologne, Cologne, iDepartment of Psychiatry and Psychotherapy, Charite Berlin, Campus Benjamin Franklin, Berlin, jDepartment of Psychiatry and Psychotherapy, University of Bonn, Bonn, kDepartment of Psychiatry, Alsterdorf Hospital, Hamburg, lDepartment of Psychiatry and Psychotherapy, University of Göttingen, Göttingen, mDepartment of Psychiatry and Psychotherapy, University of Tübingen, Tübingen, nDepartment of Psychiatry and Psychotherapy, University of Essen, Essen, and oPsychiatric Clinic, Vinzenz von Paul Hospital, Rottweil, Germany
Background: The aim of this study was to compare two measures of depression in patients with schizophrenia and schizophrenia spectrum disorder, including patients with delusional and schizoaffective disorder, to conclude implications for their application. Sampling and Methods: A total of 278 patients were assessed using the Calgary Depression Scale for Schizophrenia (CDSS) and the Hamilton Depression Rating Scale (HAMD-17). The Positive and Negative Syndrome Scale (PANSS) was also applied. At admission and discharge, a principal component analysis was performed with each depression scale. The two depression rating scales were furthermore compared using correlation and regression analyses. Results: Three factors were revealed for the CDSS and HAMD-17 factor component analysis. A very similar item loading was found for the CDSS at admission and discharge, whereas results of the loadings of the HAMD-17 items were less stable. The first two factors of the CDSS revealed correlations with positive, negative and general psychopathology. In contrast, multiple significant correlations were found for the HAMD-17 factors and the PANSS subscores. Multiple regression analyses demonstrated that the HAMD-17 accounted more for the positive and negative symptom domains than the CDSS. Conclusions: The present results suggest that compared to the HAMD-17, the CDSS is a more specific instrument to measure depressive symptoms in schizophrenia and schizophrenia spectrum disorder, especially in acutely ill patients.