DIAGNOSIS OF DEMENTIA - METHODS FOR INTERPRETATION OF SCORES OF 5 NEUROPSYCHOLOGICAL TESTS

Objective: To provide methods to interpret and compare different neuro behavioral screening tests for the diagnosis of dementia. Design: Five mental-status neuropsychological tools for dementia screening were ad ministered to patients in a memory disorder clinic. These included the Mini-Mental State Examination, the Dementia Rating Scale, the 6-item derivative of the Orientation-Memory-Concentration Test, a short Menta l Status Questionnaire, and a composite tool we labeled the Ottawa Men tal Status Examination, which assessed orientation, memory, attention, language, and visual-constructive functioning. Results: To obtain z a nd percentile scores, norms are for the different tests, computed sepa rately for patients with dementia of the Alzheimer type, vascular deme ntia, or no dementia. Another set of norms is reported in which a test score is translated directly into the posttest probability of dementi a. Translation formulas are given to allow the estimation of the score on one test from the result on another test. Conclusion: The interpre tation of tests used to diagnose dementia must be based on an understa nding of the meaning of an individual score, which is based on the que stion asked and the population to which the patient is referenced.