While a person's cognitive skills would play a role in how literate they are, the study did not examine this, Berkman said.
The findings came as no surprise to Rima Rudd, a senor lecturer at the Harvard School of Public Health who is the principal investigator for Health Literacy Studies.
While the review is sound, she says, "this offers only half the picture." The problem is not just people's low health literacy, but the inability of some health-care providers to communicate information in a way their patients can understand, Rudd said.
Rudd said patients can demand that health-care provider speak "in every day words." If you don't understand what a health-care provider is telling you, in print or in words, she suggests asking something like this: "I am sorry, but I haven't had your training. Can you use everyday words?"
Ask questions if you don't understand, Berkman added, and don't be shy about asking again and again if necessary. Taking someone with you to the doctor's office can also help, she said.
In an editorial accompanying the study, Cynthia Baur, of the U.S. Centers for Disease Control and Prevention, said the findings reinforce the idea that health communication materials have to be pre-tested with target audiences, among other practices, to be sure they are effective.
To learn more about health literacy, visit the National Network of Libraries of Medicine.
SOURCES: Rima Rudd, M.S.P.H., Sc.D., senior lecturer, Harvard School of Public Health, Boston; Nancy D. Berkman, Ph.D., senior health policy research analyst, RTI International, Research Triangle Park, N.C.; July 19, 2011, Annals of Internal Medicine
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