Age declines in numeracy: An analysis of longitudinal data.

Abstract

Numeracy, the ability to understand and use basic probability and numerical concepts, is associated with diverse positive outcomes across the lifespan. Prior cross-sectional research on numeracy has generally found a negative association with age, but positive correlations with male gender, education attainment, and measures of fluid and crystallized intelligence have been more robust. Age effects on cognitive functioning are well established, but little is known about longitudinal trends of numeracy into older age. The present study investigates longitudinal age effects on numeracy using a sample of 524 adults (2008 Agerange = 20–78) from the RAND American Life Panel. Participants completed a numeracy measure in both 2008 and 2019, a span of 11 years. Using a linear mixed-effect model to predict numeracy scores, a significant interaction between the year of testing and the quadric age term shows a decline in numeracy scores beginning in later middle age, a trend that falls in between those previously found for crystallized and fluid cognitive abilities. Numeracy declines are somewhat mitigated for males and those with higher education, but the interaction of the two variables did not return a clear pattern of results. Prior research has shown that numeracy is positively related to the quality of health and financial decisions and, ultimately, more positive health and economic outcomes. The implications of age declines in numeracy are discussed in relation to health and financial decision-making, tasks that remain relevant into old age.

Beyond High-Income Countries: Low Numeracy Is Associated with Older Adult Age around the World

“…These correlations may also reflect age-related changes: an 11-y US-wide longitudinal study found age-related declines in numeracy starting around age 60 y. 12 Indeed, theories of cognitive aging 13 suggest that age-related declines in fluid cognitive abilities may hinder numerical operations. 14,15 Low numeracy is also more common among adults with lower education, according to cross-sectional studies in high-income and upper-middle income countries.…”

“…These correlations may also reflect age-related changes: an 11-y US-wide longitudinal study found age-related declines in numeracy starting around age 60 y. 12 Indeed, theories of cognitive aging 13 suggest that age-related declines in fluid cognitive abilities may hinder numerical operations. 14 , 15 …”

“… 20 Longitudinal US-based analyses showed this pattern as well, but the low-education subsample was too small to draw confident conclusions. 12 Such longitudinal findings suggest that knowledge gained through education, or crystallized cognitive ability, may counteract age-related fluid cognitive decline. 13 Specifically, educated individuals may have learned numeric rules that they can apply to numerical problems well into older age, without relying much on fluid cognitive ability.…”