Prevalence of symptoms on the CERAD behavior rating scale for dementia in normal elderly subjects and Alzheimer's disease patients

The authors sought to define 'abnormal' levels for total scores on the CERAD Behavioral Rating Scale for Dementia (BRSD) and for 37 BRSD items by comparing 242 patients with Alzheimer's disease (AD) and 64 normal elderly control subjects (NEC). BRSD total scores for NEC ranged as high as 52 (out of a maximum 167), and although item prevalence rates were higher for AD patients, not all of these differences were significant. Many symptoms were observed in ≤10% of AD subjects. Lower Mini-Mental State Examination scores were not consistently associated with lower or higher levels of endorsement across all items. Over 6 and 12 months, endorsement rates were relatively stable for both groups. The authors conclude that assessment of behavior in long-term studies will be needed to quantify 'abnormal' levels, and that item-level BRSD information could be important in clinical trials.