Normative cognitive test performance and typical error patterns among American Indian older adults: The Strong Heart...

Area of Science:

• Neuropsychology
• Gerontology
• Public Health

Background:

• The Strong Heart Study assessed cognitive function in American Indians aged 65-95.
• Previous data indicated lower cognitive scores and higher rates of impairment in this demographic.
• Standardized neuropsychological assessments were administered at two time points (2010-2019).

Purpose of the Study:

• To define expected cognitive test score ranges for unimpaired and impaired older American Indians.
• To identify typical error patterns in cognitive assessments within this population.
• To provide benchmarks for interpreting neuropsychological test performance.

Main Methods:

• Cognitive status was determined by expert clinical review (unimpaired vs. impaired).
• Cognitive test score distributions were summarized and normalized.
• Normalization adjusted for age, sex, education, baseline cognition, bilingualism, and depression.

Main Results:

• Age, education, and baseline cognition were the primary factors influencing test score variability.
• Depression showed associations with scores on certain cognitive tests.
• Error patterns were consistent between the overall group and cognitively unimpaired individuals.

Conclusions:

• The findings offer the most accurate estimates of cognitive test performance for older American Indians.
• These benchmarks can assist clinicians and researchers in contextualizing individual patient results.
• Further research is recommended across diverse Indigenous groups, socioeconomic settings, and age ranges, including longitudinal studies.