Computerized delayed matching to sample and paired associate performance in the early detection of dementia

This study examined the ability of two computerized neuropsychological tests, delayed matching to sample and paired associate learning, to detect early dementia. Three groups of subjects classified by NINCDS-ADRDA criteria and standard neuropsychological tests were studied: normal controls, patients believed to be in early stages of dementia of the Alzheimer type, and a group of questionable dementia subjects who reported memory loss but performed normally on standard measures of cognition. All subjects completed the two computerized tests. The early dementia group performed at a significantly lower level than the other two groups on all standard and computerized measures. A linear discriminant function analysis of the computerized tests classified 100% of the normal controls and 87.5% of the dementia patients into the same groups as standard testing. The majority of questionable dementia subjects were classified as nondemented. The concurrent validity and test-retest reliability of the computerised tests were also investigated. It is suggested that computerized tests are useful when screening for early dementia, and that longitudinal studies are required to evaluate the comparative reliability of the tests.