[Short and simple is not always better: limitations of cognitive screening tests]

The increasing prevalence of Alzheimer's dementia (AD) and limited resources in outpatient care have encouraged the distribution of cognitive screening tests, in spite of their frequently unsatisfying accuracy regarding the differentiation between incipient AD, depression and age-associated memory impairment. 8 patients with probable AD and 17 controls completed a neuropsychological follow-up two years after initial examination. Beside four screening tests a memory based testing-the-limits (TtL) paradigm as well as the German version of the California Verbal Learning Test were administered. Based on hierarchical cluster analysis we could demonstrate that only well elaborated tests, such as a plasticity based TtL paradigm, did classify AD-patients correctly. The findings confirm reservations against cognitive screening procedures in detecting dementia and suggest that dynamic test strategies offer a powerful diagnostic alternative to traditional status-oriented tests.