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


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.


CONCLUSIONS
A single question may be useful for detecting patients with inadequate health literacy in a VA population.
Chew
Lisa D
LD
Department of Medicine, Division of General Internal Medicine, University of Washington, Harborview Medical Center, Seattle, WA, USA. lchew@u.washington.edu
Griffin
Joan M
JM
Partin
Melissa R
MR
Noorbaloochi
Siamak
S
Grill
Joseph P
JP
Snyder
Annamay
A
Bradley
Katharine A
KA
Nugent
Sean M
SM
Baines
Alisha D
AD
Vanryn
Michelle
M
D000368:Aged; D004522:Educational Status; D005260:Female; D007722:Health Knowledge, Attitudes, Practice; D006787:Hospitals, Veterans; D006801:Humans; D007407:Interviews as Topic; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D011795:Surveys and Questionnaires; D014481:United States