A survey diagnostic tool for senile dementia

To validate a senile dementia survey diagnostic tool, 195 individuals aged 61-91 and referred by their physicians as normal or mildly demented were examined. The etiologic diagnosis used as criterion was the consensus of two experienced neurologists, assisted by clinical and laboratory data from referring physicians and by neuropsychologic evaluation of questionably affected persons. Agreement between the neurologists was high, as indicated by a weighted Kappa coefficient of 0.97 (95% confidence interval (Cl) (0.94, 1.00)). Agreement between the instrument and criterion diagnosis was also excellent (kappa w = 0.93; 95% Cl (0.88, 0.98)). Used alone as a screening diagnostic tool, the cognitive function portion of the instrument was much more sensitive (0.929) than previously used brief tests and was acceptably specific (0.800). Because normals complete this cognitive test in 15-20 minutes, it should be a major advance in population-based studies of senile dementia and normal aging.