The validity and reliability of a Computerized Dementia Screening Test developed in Korea

Objective: This study was done to verify the validity and the reliability of the newly developed Computerized Dementia Screening Test (CDST) to be easily used in the primary care setting of Korea. Design: Comparison of the results of CDST between 103 healthy control subjects and 41 patients who were diagnosed as having mild cognitive impairment or early dementia, having a clinical dementia rate of 0.5–1 from one health examination center and two neurology clinics in university hospitals. Measurements: In order to estimate the criterion-related validity, logistic regression analysis for dementia was done using the four individual test results of CDST, age and educational level. The correlation between Korean Mini-Mental State Examination (K-MMSE) and the predicted probability of mild cognitive impairment and early dementia from the logistic regression was measured to verify its validity. The reliability of CDST was measured by test – retest reliability. Results: The sensitivity and specificity of CDST were 75.6 % and 94.2%, respectively, if the cut-off point was set to be 0.5 in the logistic regression model. The Pearson’s Correlation Coefficient between K-MMSE and the predicted probability of mild cognitive impairment and early dementia from the logistic regression analysis was 0.59 (P < 0.001). The overall test – retest reliability using the predicted probability of dementia from the logistic regression analysis of CDSTwas 0.89 (P = 0.01). Conclusion: The validity and reliability of CDST is adequate for use as a screening tool to identify mild cognitive impairment and early dementia in Korean primary care