Standardized results of the Montreal Cognitive Assessment (MoCA) for neurocognitive screening in a Chilean population

Abstract

Introduction: Population ageing poses a challenge for countries in preventing and detecting neurodegenerative disorders. The Montreal Cognitive Assessment (MoCA), a short, simple, valid, and reliable screening test, assesses general cognitive status, and is useful in public health contexts. This study aims to normalise and standardise the MoCA test for the Chilean population.

Method: We performed a descriptive, correlational validation study of the MoCA test, using a sample including 526 healthy individuals of both sexes, aged between 18 and 90 years, from the north, centre, and south of Chile. We analysed the effects of age, education level, and sex on MoCA performance.

Results: Age and education level had a significant impact on general cognitive performance, as determined by MoCA score. Age, education, and sex account for 1-7% of variance. The mean (standard deviation) score for the total sample was 24.04 (3.22), whereas the normal range originally defined for the instrument is 26-30 points. Older adults with less formal education presented poorer results and lower cognitive performance. We propose a protocol for evaluating results by percentiles and scores for different age ranges, and an individual normalised scalar score.

Discussion: We present normative data for the MoCA test in the Chilean population, and propose cut-off points for different age ranges to discriminate normal cognitive performance from neurocognitive disorders; results are adjusted for education level. This proposal would assist in the use of the test and reduce the rate of false positives.

Keywords: Cognitive screening; Cribado cognitivo; Enfermedad neurodegenerativa; Evaluación neuropsicológica; Montreal Cognitive Assessment; Neurodegenerative disease; Neuropsychological evaluation.