Date: November 14, 2025 | 11:00 AM EST / 10:00 AM CST
Duration: 1 Hour
Credits: 1
Presenter: William E. Winter, MD
Sponsor: Bio-Rad Laboratories, Inc.
Cost: Free
Hemoglobin A1c (HbA1c) testing is central to the diagnosis and management of diabetes—but only when the underlying biology, patient factors, and assay methods are properly aligned. In this webinar, we will review the essential requirements for an HbA1c result to accurately reflect a patient’s average glycemia.
Participants will gain foundational knowledge of hemoglobin biology, the biochemical basis of HbA1c formation, and the clinical and analytical factors that can compromise test validity. The webinar also highlights common sources of interference, including hemoglobin variants and altered red blood cell lifespans, and discusses when alternative markers of glycemia may be more appropriate.
Learning Objectives
At the conclusion of this webinar, participants will be able to:
- Recognize when HbA1c testing is contraindicated and when alternative glycemic markers should be used.
- Identify hematologic and clinical factors that can invalidate HbA1c measurements.
- Compare analytical HbA1c methods and their ability to detect hemoglobin variants.
About the Presenter
William E. Winter, MD, is board-certified in pediatrics, pediatric endocrinology, chemical pathology, and clinical chemistry. A Fellow of both the College of American Pathologists (CAP) and the Academy of the Association for Diagnostics and Laboratory Medicine (ADLM), Dr. Winter has served in multiple leadership roles at the University of Florida, including Director of Pathology Residency and Medical Director for Clinical Chemistry, Phlebotomy Services, and Point-of-Care Testing. He has practiced pediatric endocrinology for over 25 years and was principal investigator for several NIH-funded diabetes studies, including TrialNet, TEDDY, and RADIANT. A San Francisco native, he earned his BS in chemistry from Santa Clara University and his MD from Loyola University Chicago.
Supported in part through an unrestricted educational grant by:
Course Content
Course Includes
- 1 Lesson
- Course Certificate
MLO and Northern Illinois University (NIU), DeKalb, IL, are co-sponsors in offering continuing education units (CEUs) for this issue’s CE article. CEUs or contact hours are granted by the College of Health and Human Sciences at Northern Illinois University, which has been approved as a provider of continuing education programs in the clinical laboratory sciences by the ASCLS P.A.C.E.® program. Continuing education credits awarded for successful completion of this test are acceptable for the ASCP Board of Registry Continuing Competence Recognition Program. Readers who pass the test successfully (scoring 70% or higher) will receive a certificate for 1 contact hour of P.A.C.E.® credit. The fee for this continuing education test is $20. This test was prepared by Amanda Voelker, MPH, MT(ASCP), MLS, Clinical Education Coordinator, School of Health Studies, Northern Illinois University, DeKalb, IL.
Level of Instruction: Intermediate
Passing scores of 70 percent or higher are eligible for 1 contact hour of P.A.C.E. credit. This test is no longer valid for CEUs after November 13, 2026.
NIU is approved as a provider of continuing education programs in the clinical laboratory sciences by the ASCLS P.A.C.E. ® Program.