Diagnostic Accuracy of Persian Version of Clinical Dementia Rating (P-CDR) for Early Dementia Detection in the Elderly

According to the complications of dementia، its screening is important in elderly stage. Dementia screening tests need to have acceptable sensitivity and specificity. This study aimed at determining the cut-off point of the Persian version of Clinical Dementia Rating (P-CDR) and testing its diagnostic accuracy in the early detection of dementia among the elderly. This cross-sectional study was conducted by using the known-groups method. The purposive sampling of 50 patients with age-related dementia and 150 the elderly without dementia was recruited in kashan، Iran، 2014. The clinical interviewing and the findings of CT-Scan were used as the reference standard test. The index test was the P-CDR. A demographic questionnaire، the Geriatric Depression Scale (GDS-15)، and the P-CDR were used for data collection. The median of CDR scores in two known groups were compared using Mann-Whitney U test. The Receiver Operating Characteristic (ROC) analysis was conducted for determining the cut-off point. The diagnostic parameters were calculated for determining the diagnostic accuracy of the test with 95% confidence interval. The cognitive state scores of the elderly with and without dementia differed significantly (8. 36±1. 76 vs. 0. 82±1. 69، respectively; p< 0. 001). The area under the ROC curve was 0. 968 (p < 0. 001). The Youden’s index showed that the optimal cut-off point for the test was 3. 75. The sensitivity، specificity، positive and negative predictive values، positive and negative likelihood ratio، overall diagnostic accuracy، and diagnostic odds ratio of the test at the cut-off point of 3. 75 were 1، 0. 94، 0. 88، 1، 0، 21. 42، 0. 96، and infinity، respectively. The P-CDR is a sensitive and precise test for assessing cognitive state in the elderly. So، it can be used in dementia screening and the program of monitoring elderly people’s health.