Detection of depression in acute schizophrenia: sensitivity and specificity of 2 standard observer rating scales.
OBJECTIVE
To compare the psychometric properties of the Calgary Depression Rating Scale (CDRS) and the Hamilton Depression Rating Scale (HDRS) for severity assessment of depression in acute schizophrenia.


METHODS
During clinical routine treatment, we investigated 119 inpatients with acute schizophrenia, using the CDRS, the HDRS, and a global 4-point Depression Severity Scale (DEP-SEV). We compared CDRS and HDRS sum scores regarding their diagnostic accuracy, with global severity of depression as the criterion. We estimated sensitivity and specificity on the basis of receiver operating characteristic curves.


RESULTS
According to global clinical ratings (DEP-SEV), 31% of patients had no depression, 19% had mild, 31% had moderate, and 19% had severe depression. Sensitivity was significantly higher (P < 0.05) for the CDRS than for the HDRS to assess mild (0.94 vs 0.76, cut-off 3 vs 10 points) or severe depression (1.00 vs 0.78, cut-off 11 vs 22 points); specificity was comparably high (> or = 0.88) for both scales.


CONCLUSIONS
Despite the fact that both scales were effective in separating mild, moderate, and severe depression, significant advantages emerged for the CDRS to detect mild or severe depression in schizophrenia.
Müller
Matthias J
MJ
Department of Psychiatry, University of Mainz, Germany. mjmueller@gmx.de
Müller
Kay-Maria
KM
Fellgiebel
Andreas
A
D000208:Acute Disease; D000328:Adult; D015897:Comorbidity; D003865:Major Depressive Disorder / Q000145:classification / Q000175:diagnosis* / Q000453:epidemiology / Q000523:psychology; D005260:Female; D005858:Germany; D006801:Humans; D008297:Male; D010552:Personality Assessment / Q000706:statistics & numerical data*; D011569:Psychiatric Status Rating Scales / Q000706:statistics & numerical data*; D011594:Psychometrics / Q000706:statistics & numerical data; D012372:ROC Curve; D015203:Reproducibility of Results; D012559:Schizophrenia / Q000175:diagnosis* / Q000453:epidemiology; D013223:Statistics as Topic