Use of the MoCA in Detecting Early Alzheimer's Disease in a Spanish-Speaking Population with Varied Levels of Education

Abstract

Background/Aims: Performance on the Montreal Cognitive Assessment (MoCA) has been demonstrated to be dependent on the educational level. The purpose of this study was to identify how to best adjust MoCA scores and to identify MoCA items most sensitive to cognitive decline in incipient Alzheimer's disease (AD) in a Spanish-speaking population with varied levels of education. Methods: We analyzed data from 50 Spanish-speaking participants. We examined the pattern of diagnosis-adjusted MoCA residuals in relation to education and compared four alternative score adjustments using bootstrap sampling. Sensitivity and specificity analyses were performed for the raw and each adjusted score. The interval reliability of the MoCA as well as item discrimination and item validity were examined. Results: We found that with progressive compensation added for those with lower education, unexplained residuals decreased and education-residual association moved to zero, suggesting that more compensation was necessary to better adjust MoCA scores in those with a lower educational level. Cube copying, sentence repetition, delayed recall, and orientation were most sensitive to cognitive impairment due to AD. Conclusion: A compensation of 3-4 points was needed for <6 years of education. Overall, the Spanish version of the MoCA maintained adequate psychometric properties in this population.