An investigation of the efficiency of the mini-Kingston standardized cognitive assessment-revised in classifying patients according to DSM-5 major and mild neurocognitive disorders due to possible Alzheimer's disease

Background: The aim of this study was to examine the efficiency of the mini-Kingston standardized cognitive assessment-revised (mini-KSCAr) in classifying patients according to DSM-5 major and mild neurocognitive disorders (NCD) due to possible Alzheimer's disease (AD). Methods: Files of 85 individuals who were tested on the Kingston standardized cognitive assessment-revised were reviewed and scores were calculated for the mini-KSCAr. Medical history, psychiatric and physical status, basic and instrumental activities of daily living, as well as scores on the Cambridge cognitive examination-revised (CAMCOG-R), and the clinical dementia rating (CDR) scale were used to establish DSM-5 diagnoses of major or mild neurocognitive disorders (NCD) due to possible AD or no cognitive decline. All participants were tested on the Mini-Mental State Examination (MMSE) and the clock drawing test (CDT), and a subset (N = 28) were also tested on three well-known memory tasks. Results: Scores on the MMSE, CDT, and mini-KSCAr differed across groups, but only the mini-KSCAr significantly distinguished each group from the other two. The mini-KSCAr showed better sensitivity, specificity, and likelihood ratios (LRs) than did the MMSE and the CDT. A regression analysis revealed that the mini-KSCAr accounted for almost half of the variance in memory performance, whereas the MMSE and the CDT contributed nothing to this prediction once the mini-KSCAr was used. Conclusions: The mini-KSCAr is an efficient instrument for the diagnosis of DSM-5 major and mild NCD due to possible AD in a specialized psychogeriatric setting, and its utility is greater than that of the MMSE and the CDT.