Effect of literacy level on cognitive and language tests in Korean illiterate older adults

Illiterate individuals represent a significant proportion of the world's population. Acquisition of reading and writing skills influences the functional status of the brain, and consequently alters the performance on cognitive and language tests. Thus, it is important to identify the degree of the impact of levels of both illiteracy and education as potential confounders on test performance in people with neurological communication disorders.

A total of 203 community-dwelling older adults aged 65 years and older were recruited for the present study. Participants were classified into four groups based on the literacy level; pure illiterate (n=29), semi-illiterate (n=67), literate (n=75) and high-level literate (n=32). The participants completed the Mini-Mental State Examination, Boston Naming Test, Controlled Oral Word Association Test (animal), verb naming, and sentence comprehension tests.

The pure illiterate group showed the lowest performance on all five tests. Regression analysis showed that literacy level was the variable that best predicted the performance on cognitive and language tests.

These findings suggest that literacy in performance on cognitive and language tests is an important factor in neuropsychological evaluations for older adults.