EFFECTS OF SEQUENTIAL NEUROPSYCHOLOGICAL TESTING OF AN ELDERLY COMMUNITY-BASED SAMPLE

The magnitude and importance of changes in scores of neuropsychologica l tests on retest in the elderly, especially over long time periods, i s not well established. Three neuropsychological tests and one mental status test were initially administered to screen for potential dement ia and were readministered to 380 of the surviving individuals 2.4 yea rs later who either failed the screening examination or were an age ma tched control. Of the 380 women and men aged 65 and older, 56 were dia gnosed as having Alzheimer disease (AD), 82 as at risk for developing AD, and 242 as having normal cognition. The present report focuses on changes in test scores between the two visits. In the normal and at ri sk groups, significant improvements were seen on retest of the Visual Reproduction Test (VRT), the Trails B test, and the Mini-Mental Status examination; verbal fluency decreased, and savings score of the VRT s howed small variations. On most tests, scores of the AD group decrease d. Practice effects, biases, and other variables may have played a rol e in the improvements seen in those labeled normal and at risk. If the se results are confirmed, savings score of the VRT (which remained sta ble over time in normals and individuals at risk and decreased in pati ents with dementia) and verbal fluency (which decreased in all groups) may be better measures of true cognitive performance than the other t ests that we evaluated.