Validation of screening questions for limited health literacy in a large VA outpatient population

J Gen Intern Med. 2008 May;23(5):561-6. doi: 10.1007/s11606-008-0520-5. Epub 2008 Mar 12.

Abstract

Objectives: Previous studies have shown that a single question may identify individuals with inadequate health literacy. We evaluated and compared the performance of 3 health literacy screening questions for detecting patients with inadequate or marginal health literacy in a large VA population.

Methods: We conducted in-person interviews among a random sample of patients from 4 VA medical centers that included 3 health literacy screening questions and 2 validated health literacy measures. Patients were classified as having inadequate, marginal, or adequate health literacy based on the Short Test of Functional Health Literacy in Adults (S-TOFHLA) and the Rapid Estimate of Adult Literacy in Medicine (REALM). We evaluated the ability of each of 3 questions to detect: 1) inadequate and the combination of "inadequate or marginal" health literacy based on the S-TOFHLA and 2) inadequate and the combination of "inadequate or marginal" health literacy based on the REALM.

Measurements and main results: Of 4,384 patients, 1,796 (41%) completed interviews. The prevalences of inadequate health literacy were 6.8% and 4.2%, based on the S-TOHFLA and REALM, respectively. Comparable prevalences for marginal health literacy were 7.4% and 17%, respectively. For detecting inadequate health literacy, "How confident are you filling out medical forms by yourself?" had the largest area under the Receiver Operating Characteristic Curve (AUROC) of 0.74 (95% CI: 0.69-0.79) and 0.84 (95% CI: 0.79-0.89) based on the S-TOFHLA and REALM, respectively. AUROCs were lower for detecting "inadequate or marginal" health literacy than for detecting inadequate health literacy for each of the 3 questions.

Conclusion: A single question may be useful for detecting patients with inadequate health literacy in a VA population.

Publication types

  • Multicenter Study
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Validation Study

MeSH terms

  • Aged
  • Educational Status
  • Female
  • Health Knowledge, Attitudes, Practice*
  • Hospitals, Veterans
  • Humans
  • Interviews as Topic
  • Male
  • Middle Aged
  • ROC Curve
  • Surveys and Questionnaires*
  • United States