Practice effects: a unique cognitive variable.

Practice effects are improvements in cognitive test performance due to repeated evaluation with the same or similar test materials. Prior studies have reported that these improvements can vary with age, education/intellect, and disease status. However, additional information is needed about variables that influence practice effects. The current study prospectively quantified short-term practice effects in 268 community-dwelling older adults and compared these practice effects to demographic variables, global cognition, premorbid intellect, depression, and individual cognitive domains. Overall, practice effects were not significantly related to most demographic and clinical characteristics or individual cognitive domains, which was contrary to our hypotheses. However, since practice effects appear to be uninfluenced by many variables that typically affect cognitive scores, they may be a unique and valuable tool that could be applied in a number of diverse patient groups.