Poor Numeracy Is Common and Might Be Associated with Worse Glycemic Control

Health advice often involves the use of numbers. Researchers surveyed 398 patients with diabetes to determine their levels of health literacy, general numeracy, and diabetes-related numeracy and assessed how numeracy affected glycemic control (most recent glycosylated hemoglobin [HbA_1c] level).

The median score on a diabetes numeracy test was 65%. Only 38% of patients understood titration instructions for a long-acting insulin regimen, 44% correctly calculated the grams of carbohydrates in a bag of snack chips, 66% correctly marked 54 units on a 100-unit syringe, and 74% identified glucose levels within the target range of 60 mg/dL to 120 mg/dL. Low literacy and low general numeracy were associated with low diabetes-specific numeracy. Patien…