Clinical utility of a brief screen for health literacy and numeracy among adults with diabetes mellitus.

BACKGROUND AND OBJECTIVES Our objectives were to (1) compare Newest Vital Sign (NVS) scores and administration characteristics with the short (S) version of the Test of Functional Health Literacy in Adults (S-TOFHLA) and Spoken Knowledge in Low-Literacy Diabetes (SKILLD) tool and (2) gather information from research assistants (RAs) regarding their perceptions of patient understanding of NVS items. METHODS Adults, age ? 18 years, with diabetes mellitus visiting a primary care clinic were recruited to participate. An RA orally administered a sociodemographic questionnaire. Patients completed, in random order, the NVS, S-TOFHLA, and SKILLD. Completion time for each tool was electronically recorded, while patients assessed tool difficulty using a 5-point Likert-type scale. RAs' comments regarding patients' understanding of individual NVS items were tallied. RESULTS A total of 226 patients (mean age=53.8 years, 31% male, 45.1% African American, 28.8% high school graduate) participated. African Americans were significantly less likely to score ?4 on the NVS (adjusted OR=0.23, 95% CI=0.13, 0.42) as compared to Caucasians. NVS scores were highly correlated with S-TOFHLA scores, rho=0.62, and moderately correlated with SKILLD scores, rho=0.39. NVS scores were inversely correlated with completion time, rho=-0.25 and difficulty rating, rho=-0.37. CONCLUSIONS Related to the care of patients with diabetes, the most important feature of the NVS is that it can quickly provide a clinician with valuable insight regarding their patients' ability to complete a practical skill (ie, interpreting a food label) needed to achieve tight blood glucose control.