Abstract
Objective
To impute limited health literacy from commonly measured socio-demographic data and to compare it to the Short-Test of Functional Health Literacy in Adults (S-TOFHLA) for estimating the influence of limited health literacy on health status in the elderly.
Methods
The Prudential Medicare Study assesses the S-TOFHLA score, leading to a “reference standard” classification of 25% of people with inadequate literacy; the National Health Interview Survey has no such assessment. We estimated a regression of S-TOFHLA on sex, age, years of schooling, and race/ethnicity in The Prudential Medicare Study data to derive a Demographic Assessment for Health Literacy (DAHL) score, and imputed inadequate literacy to the 25% with the lowest DAHL scores. Using regression, we then examined associations between several health status measures (including hypertension, diabetes, physical and mental SF-12) and inadequate literacy (imputed or test-based).
Results
Estimates of association using imputed inadequate literacy closely approximate those obtained using S-TOFHLA-based inadequate literacy for most outcomes examined.
Conclusions
As few population surveys measure health literacy, the DAHL, a readily calculated health literacy proxy score, may be useful for expanding the scope of health literacy research in national survey data.


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Acknowledgements
The findings of this study were presented at the 2007 Annual Meetings of both the Society of General Internal Medicine (April 25–28, Toronto) and the AcademyHealth (June 3–5, Orlando, FL).
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Hanchate, A.D., Ash, A.S., Gazmararian, J.A. et al. The Demographic Assessment for Health Literacy (DAHL): A New Tool for Estimating Associations between Health Literacy and Outcomes in National Surveys. J GEN INTERN MED 23, 1561–1566 (2008). https://doi.org/10.1007/s11606-008-0699-5
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DOI: https://doi.org/10.1007/s11606-008-0699-5