Validation and diagnostic utility of the dementia rating scale in a mixed dementia population.

The Dementia Severity Rating Scale (DSRS), a previously validated caregiver-based measure assessing dementia severity, was recently revised to improve clarity. Our study aims included: (1) identifying the DSRS factor structure, (2) examining the relation between neuropsychological measures, the Mini-Mental State Examination, and clinical diagnoses with the DSRS, and (3) determining the clinical utility of the DSRS in a mixed clinical sample. A total of 270 veterans were referred to a cognitive disorders clinic at a VA medical center and completed neuropsychological, affective, and cognitive screening measures. Caregivers completed the DSRS. Principal components analysis identified a 2-factor solution. After controlling for age and education, memory and language were related to the Cognitive factor, whereas attention, processing speed, visuospatial processing, and executive functioning were related to both Cognitive and Self-Care factors. Neither factors correlated with depression. The total DSRS score was able to differentiate patients by the Mini-Mental State Examination scores and diagnoses of mild cognitive impairment and dementia (mixed vascular Alzheimer, vascular dementia, and Alzheimer disease). A cut-score >15 was optimal for detecting dementia in a mixed clinical sample (sensitivity=0.41, specificity=0.79), with a posttest probability of 74%. This study suggests that the DSRS improves detection of dementia and requires minimal effort to implement.