Combining cognitive screening tests for the evaluation of mild cognitive impairment in the elderly.
OBJECTIVE
To determine the accuracy of the Mini-Mental State Examination combined with the Verbal Fluency Test and Clock Drawing Test for the identification of patients with mild cognitive impairment and Alzheimer's disease (AD).


METHODS
These tests were used to evaluate cognitive function in 247 older adults. Subjects were divided into three groups according to their cognitive state: mild cognitive impairment (n=83), AD (n=81), cognitively unimpaired controls (n=83), based on clinical and neuropsychological data. The diagnostic accuracy of each test for discriminating between these diagnostic groups (mild cognitive impairment or AD vs. controls) was examined with the aid of Receiver Operating Characteristic (ROC) curves. Additionally, we evaluated the benefit of the combination of tests on diagnostic accuracy.


RESULTS
Although they were accurate enough for the identification of Alzheimer's disease, neither test alone proved adequate for the correct separation of patients with mild cognitive impairment from healthy subjects. Combining these tests did not improve diagnostic accuracy, as compared to the Mini-Mental State Examination alone, in the identification of patients with mild cognitive impairment or Alzheimer's disease.


CONCLUSIONS
The present data do not warrant the combined use of the Mini-Mental State Examination, the Verbal Fluency Test and the Clock Drawing Test as a sufficient diagnostic schedule in screening for mild cognitive impairment. The present data do not support the notion that the combination of test scores is better that the use of Mini-Mental State Examination scores alone in the screening for Alzheimer's disease.
Laboratory of Neuroscience-LIM 27, Institute of Psychiatry, Faculdade de Medicina da Universidade de São Paulo, São Paulo, SP, Brazil.
Rodolfo B
RB
Ladeira
Breno S
BS
Diniz
Paula V
PV
Nunes
Orestes V
OV
Forlenza
D000368:Aged; D000544:Alzheimer Disease / Q000175:diagnosis*; D003072:Cognition Disorders / Q000175:diagnosis*; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D008297:Male; D008609:Mental Status Schedule / Q000592:standards; D009483:Neuropsychological Tests / Q000592:standards*