Bolus Insulin Dose Error Distributions Based on Results From Two Clinical Trials Comparing Blood Glucose Monitoring Systems

Background: In 2 previous clinical trials, fingertip capillary blood samples were evaluated using prespecified blood glucose monitoring systems (BGMSs) and a reference YSI glucose analyzer. In post hoc analyses, hypothetical insulin doses were calculated using these blood glucose measurements; dosing errors were compared for each trial. Method: For each blood glucose measurement, premeal bolus insulin dosing was determined for a hypothetical person, assuming a 60-g carbohydrate meal and 100-mg/dL target blood glucose level (adjusting 1/25 insulin sensitivity and 1/15 insulin:carbohydrate ratio inputs to account for BGMS measurement error). Dosing error was the difference between doses calculated using the BGMS and YSI results. Results: In Clinical Trial 1, 95% dose error ranges (in units of insulin) were: CONTOUR®NEXT EZ BGMS (EZ), –0.9 to 0.5; Accu-Chek® Aviva BGMS (ACA), –0.5 to 1.8; FreeStyle Freedom Lite® BGMS (FFL), –3.2 to −0.3; OneTouch® Ultra®2 BGMS (OTU2), –4.1 to 0.3; and Truetrack® BGMS (TT), –3.9 to 2.2. In Clinical Trial 2, these ranges were: CONTOUR®NEXT BGMS (CN), –0.7 to 1.7; Accu-Chek® Aviva Nano BGMS (ACAN), –1.3 to 1.8; FreeStyle Lite® BGMS (FSL), –5.1 to 0.2; OTU2, –1.9 to 1.2; OneTouch® Verio® Pro BGMS (OTVP), –1.0 to 1.9; and TT, –5.1 to 1.7. Within each trial, EZ and CN had statistically significantly smaller insulin dose error ranges than other BGMSs (P