Brief screening for mild cognitive impairment: validation of the Brazilian version of the Montreal cognitive assessment

Abstract

Background The Montreal Cognitive Assessment (MoCA) is a brief cognitive schedule that has been developed for the screening of patients with Mild Cognitive Impairment (MCI). MCI is recognized as a high-risk state for Alzheimer's disease. The aim of the present study is to examine the reliability and validity of the Brazilian version of the MoCA test (MoCA-BR) in a sample of older individuals with at least 4?years of education. Methods The MoCA-BR was administered to 112 older adults who were classified into three diagnostic groups according to their cognitive state (Alzheimer's disease, n?=?28; MCI, n?=?43; normal controls, n?=?41). This procedure was based on clinical and neuropsychological data. The performance in the MoCA-BR was compared with the Mini-mental state examination (MMSE) and the Cambridge Cognitive Examination. Diagnostic accuracy was examined with the receiver operating characteristic (ROC) curve analyses. Results Cronbach's alpha for the MoCA-BR was 0.75. Temporal stability (retesting after 3?months) using intraclass correlation coefficient was 0.75 (p?<?0.001). The sensitivity and specificity of the MoCA-BR for MCI were 81% and 77%, respectively, with a cut-off score of 25 points. The area under the ROC curve for predicting MCI was 0.82?+/-?0.06. Conclusions The present results indicate that the MoCA-BR maintains its core diagnostic properties rendering it a valid and reliable tool for the screening of MCI among older individuals with at least 4?years of education.