Premorbid intellect and current RBANS performance: discrepancy scores in three geriatric samples.

Assessing cognitive change during a single visit requires the comparison of estimated premorbid abilities and current neuropsychological functioning. As newer instruments are developed to measure current cognitive functioning, their relationships with premorbid estimates need to be evaluated. The current study examined the clinical utility of discrepancy scores between an estimate of premorbid intellect derived from demographic variables (i.e., Barona) and the Total score on the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) in three geriatric samples. A large community-dwelling "control" sample and two clinical samples were examined. As expected, there was little difference between estimated premorbid intellect and current RBANS Total Scale scores in the community-dwelling sample, while estimated premorbid intellect obtained from the two clinical samples significantly differed from obtained RBANS Total scores. Similar findings were observed on Discrepancy scores for the five Indexes of RBANS. The current findings, along with normative data on these discrepancy scores, can provide additional confidence for clinicians and researchers who need to determine cognitive decline when using these screening measures of neuropsychological status.