Formal education level versus self-rated literacy as predictors of cognitive aging.

OBJECTIVES To compare the prediction of cognitive functioning by formal education and self-rated literacy and the differences in prediction across younger and older cohorts. METHOD Data on 28,535 respondents were drawn from a cross-sectional representative sample of community-dwelling older individuals (≥50), participating in the Survey of Health, Ageing, and Retirement in Europe. Education level was classified according to the International Standard Classification of Education 1997 (ISCED-1997) self-rated literacy was determined by having respondents rate their reading and writing on 1-5 scales. Cognitive functioning was measured by verbal recall, word fluency, and arithmetic ability. RESULTS Structural equation modeling demonstrated that self-rated literacy was more strongly associated with cognitive functioning than was education level, with or without additional exogenous variables (age, sex, household income, medical conditions, activities of daily living, reading eyesight, and country). The association between education level and cognitive functioning was weaker in older than in younger age groups, whereas the association between self-rated literacy and cognitive functioning showed the opposite trend. DISCUSSION Self-rated literacy was found to be a better predictor of late-life cognitive functioning than was the level of formal education. The results have implications for studies of age-related differences in which education level is taken into account.