A Comparison of Two Depression Scales in a Geriatric Assessment Clinic

Two commonly used geriatric depression rating scales are the Geriatric Depression Scale (GDS) and the Cornell Scale for Depression in Dementia (CS). The GDS is a self-rating scale used to identify depressed older adults, whereas the CS is used to assess severity of depression based on a clinical interview. Because the scales may thus be complementary, their use was examined in 182 patients undergoing an outpatient geriatric assessment. Geriatric psychiatrists, blind to the results of the GDS, completed the CS and assigned clinical diagnoses. Both scales distinguished depressed from nondepressed individuals by means of ROC-generated cutoff scores relative to a clinical diagnosis of depression. The scores on the depression scales were not affected by cognitive status as measured by the Mini-Mental State Examination. The mean GDS scores did not vary by geriatric psychiatrist. The mean CS scores, however, did significantly differ across psychiatrists despite the fact that the psychiatrists were not blind to patients' clinical diagnosis.