Neuropsychological prediction of attrition due to death.

In aging research, attrition bias produces underestimates of cognitive decline and limits the interpretation of cognitive change. Using data from the Canadian Study of Health and Aging, we identified neuropsychological predictors of death among not cognitively impaired (NCI) and cognitively impaired, not-demented (CIND) persons. For those with NCI, two neuropsychological measures significantly predicted attrition, over and above age, in the short term, while age was the best long-term predictor. The absence of neuropsychological predictors for the CIND group may reflect the group's etiological heterogeneity. In future research, the use of a more homogeneous subset of CIND may yield additional predictors.