ABCs or 123s? The independent contributions of literacy and numeracy skills on health task performance among older adults.
OBJECTIVE
To investigate the relationship between literacy and numeracy and their association with health task performance.


METHODS
Older adults (n=304) completed commonly used measures of literacy and numeracy. Single factor literacy and numeracy scores were calculated and used to predict performance on an established set of health self-management tasks, including: (i) responding to spoken information; (ii) comprehension of print and (iii) multimedia information; and (iv) organizing and dosing medication. Total and sub-scale scores were calculated.


RESULTS
Literacy and numeracy measures were highly correlated (rs=0.68; ps<0.001). In multivariable models adjusted for age, gender, race, education, and comorbidity, lower literacy (β=0.44, p<0.001) and numeracy (β=0.44, p<0.001) were independently associated with worse overall task performance and all sub-scales (literacy range, β=0.23-0.45, ps<0.001; numeracy range, β=0.31-0.41, ps<0.001). Multivariable analyses with both constructs entered explained more variance in overall health task performance compared with separate literacy and numeracy models (8.2% and 10% respectively, ps<0.001).


CONCLUSIONS
Literacy and numeracy were highly correlated, but independent predictors of health task performance. These skill sets are complementary and both are important for health self-management.


CONCLUSIONS
Self-management interventions may be more effective if they consider both literacy and numeracy skills rather than focusing on one specific ability.
Health Literacy and Learning Program, Division of General Internal Medicine and Geriatrics, Northwestern University, Chicago, USA; Wolfson Institute of Preventive Medicine, Queen Mary University of London, London, UK. Electronic address: Samuel.smith@ucl.ac.uk.
Samuel G
SG
Smith
Health Literacy and Learning Program, Division of General Internal Medicine and Geriatrics, Northwestern University, Chicago, USA.
Laura M
LM
Curtis
Health Literacy and Learning Program, Division of General Internal Medicine and Geriatrics, Northwestern University, Chicago, USA.
Rachel
R
O'Conor
Division of General Internal Medicine, Mount Sinai School of Medicine, New York, USA.
Alex D
AD
Federman
Health Literacy and Learning Program, Division of General Internal Medicine and Geriatrics, Northwestern University, Chicago, USA; Department of Learning Sciences, Northwestern University, Chicago, USA.
Michael S
MS
Wolf
D000368:Aged; D032882:Comprehension; D003430:Cross-Sectional Studies; D003657:Decision Making; D005260:Female; D015438:Health Behavior; D058015:Health Communication; D007722:Health Knowledge, Attitudes, Practice; D057220:Health Literacy; D006801:Humans; D007407:Interviews as Topic; D008297:Male; D008433:Mathematics; D008875:Middle Aged; D015999:Multivariate Analysis; D010353:Patient Education as Topic; D012648:Self Care; D011795:Surveys and Questionnaires; D013647:Task Performance and Analysis
Health communication; Health literacy; Numeracy; Patient education