Abstract

Dementia, with its associated morbidity and mortality, has emerged as a leading public health problem with elderly persons and its early detection is of obrious importance for treatment in curable cases and referral of patients to optimal medical facilities with education support for family members. While the precision of detecting demented subjects by the existing screening methods has improved in recent years, they are still complex and time consuming in practice and therefore difficult to use. We have developed an screening method adapted for Japanese based on "The Time and Charge Test" of Froehlich and coworkers. The time test evaluates the understanding of clock hands indicating 11:10, and the charge test the ability selecting 100 yen from a group of coins consisting of one 50-yen coin, seven 10-yen coins and seven 5-yen coins. This test was conducted on 40 persons (two out of whom dropped out) living in Roken facility (a health facility for the elderly) and another 40 visiting a day care center for the elderly. The test results were studied using Mini-Mental State Examination and Hasegawa's Dementia Scale-revised version. The sensitivity of our test was 49.1%, the specificity 95.2%, the negative predictive value 40.8%, and the positive predictive value 96.6%. When a time limit 5 seconds for completing the task for the time test and 20 seconds for the charge test, the sensitivity was 87.7%, the specificity 57.1% the negative predictive value 63.2%, and the positive predictive value 84.7%. As for reproducibility, test-retest gave a value of 85.0%, and the inter-observer agreement was 89.5%. This simple method thus appears useful for screening for dementia.