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.