Performance on the CERAD Word List Memory task: a comparison of university-based and community-based groups.

BACKGROUND: Evaluation of patients for Alzheimer's disease often compares an individual's performance on cognitive tests to established norms. The purpose of this study was to compare performance on the CERAD Word List Memory tasks in normal controls from an Alzheimer's disease registry and in community volunteers. METHODS: Scores on Word List Memory tasks were evaluated in cognitively intact participants enrolled in a university-based Alzheimer's disease registry (n=103) and in a sample of community volunteers (n=51). Scores for the two samples were also compared with previously published data from registry-based normal controls and from a representative community-based sample. RESULTS: University-based participants outperformed community volunteers, with most marked differences on Delayed Recall and on a Savings score that contrasted immediate to delayed recall. University-based participants performed similarly to previously published scores for normal controls from another university-based Alzheimer's disease registry, while community volunteers were consistent with published scores available from a representative community sample. CONCLUSIONS: Accurate neuropsychological assessment of Alzheimer's disease may require consideration of potentially subtle differences between older adults tested at university centers and those tested in the community.