The National Glycohemoglobin Standardization Program: Over 20 Years of Improving Hemoglobin A1c Measurement

Measurement of hemoglobin A1c in blood is essential for the management of patients with diabetes mellitus.  Hemoglobin A1c reflects the average blood glucose concentration over the proceeding 8 to 12 weeks.  While the clinical value of hemoglobin A1c was initially limited by large differences in results among various methods, the investment of considerable effort to implement standardization has brought about a marked improvement in analysis. In the July 2019 issue of Clinical Chemistry, a Review article chronicles the substantial progress that has been achieved in enhancing the accuracy of these measurements and the role of the National Glycohemoglobin Standardization Program in those efforts.