Concordance of Central Laboratory Hemoglobin A1c Measurements from Capillary Kits Compared to Venous Draws in the Insulin-Only Bionic Pancreas Pivotal Trial.

ABSTRACT

Capillary hemoglobin A1c (HbA1c) collection has grown in importance due to its convenience during situations such as the coronavirus disease 2019 (COVID-19) pandemic and virtual visits. The viability of capillary blood samples as an accurate alternative to venous samples has previously only been assessed in smaller sample sizes. In this brief report, 773 paired capillary and venous samples taken from 258 study participants in the Insulin-Only Bionic Pancreas Trial were analyzed at the University of Minnesota Advanced Research and Diagnostic Laboratory and assessed for HbA1c value congruency. Results showed that 97.7% of the capillary samples were within 5% of their respective venous measurement, and R2 between the two HbA1c sources was 0.95. These results are consistent with previous studies that also reported high concordance between capillary and venous HbA1c values using the same laboratory method, providing further evidence that capillary HbA1c measurements are an accurate alternative to venous measurements. Clinical Trial Registration number NCT04200313.