Effectiveness of the Takeda Three Colors Combination Test as a screening test for dementia

Background:  The aged population is increasing worldwide and it is expected that dementia, for which aging is a risk factor, will increase as well. A critical issue then becomes a community's capacity for the early detection of dementia among its senior citizens. In the present paper, we report on the development and potential use of a screening test for dementia that can be administered and assessed easily in a short period of time by non-specialist clinicians and represents no burden for those undergoing the screening. Methods:  Three hundred and sixty senior citizens, over 60 years of age, participated in the study. Of these, 126 had Alzheimer's disease (AD), 60 had vascular dementia (VaD), 41 had mild cognitive impairment (MCI), and 133 were healthy volunteers (control group). A screening test for dementia, which consisted of a colored cards configuration memory task (the Takeda Three Colors Combination Test; TTCC) was examined for sensitivity, specificity, reliability and criterion-related validity. Results:  Sufficient sensitivity and specificity were demonstrated for each clinical group (AD, VaD) and the control group. The sensitivity of the TTCC was 0.94, 0.82, and 0.71 for the AD, VaD, and MCI groups, respectively; specificity was 0.83. In addition, sufficient reliability and validity were established. Administration of the TTCCand assessment procedures required only 1 or 2 min. Conclusion:  Satisfactory sensitivity and specificity were indicated for both the AD and VaD groups, with sufficient reliability and validity also indicated. Thus, the TTCC is an effective dementia screening test.