Published online by Cambridge University Press: 14 October 2020
Normative data should consider sociodemographic diversity for the accurate diagnosis of cognitive impairment. This study aims to provide normative data for a brief neuropsychological battery and present diagnostic criteria for cognitive impairment that could be used in primary care settings.
We selected 9618 Brazilian middle-aged and older adults after detailed exclusion criteria to avoid subtle cognitive impairment. We analyzed age, sex, and education influence on cognitive performance. To verify the evidence of criterion validity, we compared the cognitive performance of subjects with and without a depressive episode. Additionally, we verified the percentage of spurious scores under three different cutoffs.
Age and education had the greatest impact on cognition. Normative scores were provided according to age and education groups. Participants with a depressive episode performed poorer than control subjects. The clinical cutoff of at least two scores below the 7th percentile revealed the adequate percentage of spurious and possible clinical performance.
The Longitudinal Study on Adult Health (ELSA-Brasil) provided normative data based on a unique selected set of cognitively normal subjects. Normative groups were selected based on age and education, and the battery was sensitive to the presence of a depressive episode. We suggested clinical cutoffs for the tests in this battery that could be used in primary care settings to improve the accurate diagnosis of cognitive impairment.