Screening for Alzheimer's disease: the memory impairment screen versus the conventional three-word memory test

OBJECTIVES: To improve screening for Alzheimer's disease (AD) with the Memory Impairment Screen (MIS), a 4-minute, four-item delayed free and cued recall memory test with controlled learning and high discriminative validity. To assess the discriminative validity of the MIS for AD and to compare it with the conventional three-word memory test, a delayed free recall task, widely recommended as a dementia-screening test in clinical practice. DESIGN: Cross-sectional validation study nested within a longitudinal study of aging and dementia. The MIS and the standard three-word memory task were administered as part of a comprehensive neurological and neuropsychological evaluation. SETTING: Einstein Aging Study at the Albert Einstein College of Medicine, Bronx, New York. PARTICIPANTS: Two hundred forty community-dwelling older adults. MEASUREMENTS: Sensitivity, specificity, and positive predictive value (PPV) were calculated for the MIS and three-word memory test as screening tests for AD. RESULTS: In comparison with the three-word memory task, the MIS had higher sensitivity (.86 vs.65), higher specificity (.97 vs.85), and greater PPV (.80 vs.37) as a screen for AD. CONCLUSIONS: The MIS had high discriminative validity as a screening test for AD and substantially outperformed the three-word memory task. Given its validity and brevity, the MIS has important advantages as an AD screen for use in primary care.