Influence of demographic variables on the Dementia Rating Scale.

Demographic characteristics influence many cognitive assessment tools. We evaluated the impact of age, education, and gender on the Dementia Rating Scale (DRS) in a sample of 212 normal people. Separate regression analyses revealed that age was the most potent demographic factor, whereas education and gender had little impact. However, the amount of variance accounted for by age was small (less than 20%). Clinical utility of age-adjusted DRS total score cut-offs was investigated in samples of Alzheimer's and Parkinson's disease patients. Hit rate analysis revealed greater sensitivity for a single cut-off value than age-corrected cut-off scores. Overall, these findings revealed the lack of a clinically meaningful relationship between demographic characteristics and DRS scores, suggesting that age, education, and gender can be ignored for interpretative purposes based on cut-off scores.