Numeracy is an important but understudied component of health literacy (HL). The purpose of this study was to examine the predictive ability of established general HL and numeracy screening items in estimating Newest Vital Sign (NVS) scores.Methods
We studied 241 adults attending primary care clinics in the midwestern United States. Demographic items, HL screening questions, and the NVS were administered to patients. To determine the accuracy of HL and numeracy screening items, area under the receiver operating characteristic (AUROC) curves were determined for each screening item, using NVS scores as the reference standard.Results
Patients' mean age was 46.1 ± 16.3 years; 71.0% were female, 53.4% were African American, 7.5% had less than a high school education, and 44.4% were insured by Medicaid/Medicare. The mean NVS score was 3.7 ± 2.0, with 17.8% classified as having inadequate HL/numeracy (NVS score of 0 or 1). The HL screening item, “How confident are you filling out medical forms by yourself?” was the best predictor of both limited (AUROC, 0.83; 95% confidence interval [CI], 0.76–0.89) and limited/marginal (AUROC, 0.79; 95% CI, 0.73–0.85) NVS scores. The numeracy screening item, “In general, how easy or hard do you find it to understand medical statistics?” was the best predictor of both limited (AUROC, 0.83; 95% CI, 0.76–0.89) and limited/marginal (AUROC = 0.78; 95% CI, 0.72–0.84) NVS scores.Conclusion
Brief HL and numeracy screening items are useful for quickly estimating NVS scores among English-speaking primary care clinic populations.