Does literacy mediate the relationship between education and health outcomes? A study of a low-income population with diabetes

Public Health Rep. 2006 May-Jun;121(3):245-54. doi: 10.1177/003335490612100305.


Objectives: We sought to determine whether literacy mediates the relationship between education and glycemic control among diabetes patients.

Methods: We measured educational attainment, literacy using the Short Test of Functional Health Literacy in Adults (s-TOFHLA), and glycemic control (HbA1c) in 395 diabetes patients at a U.S. public hospital. We performed path analysis to compare two competing models to explain glycemic control. The direct effects model estimated how education was related to HbA1c; the mediational model estimated the strength of the direct relationship when the additional pathway from education to literacy to HbA1c was added.

Results: Both the model with a direct effect of education on HbA1c and the model with literacy as a mediator were supported by good fit to observed data. The mediational model, however, was a significant improvement, with the additional path from literacy to HbA1c reducing the discrepancy from observed data (p < 0.01). After including this path, the direct relationship between education and HbA1c fell to a non-significant threshold.

Conclusions: In a low-income population with diabetes, literacy mediated the relationship between education and glycemic control. This finding has important implications for both education and health policy.

Publication types

  • Multicenter Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Diabetes Mellitus / blood*
  • Educational Status*
  • Glycemic Index*
  • Health Status*
  • Humans
  • Insurance, Health
  • Male
  • Middle Aged
  • Models, Biological
  • Poverty*
  • San Francisco
  • Surveys and Questionnaires