The Diabetes Diagnostic Laboratory (DDL) specializes in state-of-the-art diabetes-related testing for projects ranging from small-scale research studies to long-term, large-scale clinical trials. We provide the finest quality diagnostic testing and the clinical knowledge and experience to benefit clients and patients through our unique integration of clinical and laboratory expertise.

Our primary test is Hemoglobin A1c (HbA1c), which is a measure of the amount of glucose attached to hemoglobin (Hb) in red blood cells. The higher the glucose levels over the previous 2-3 months, the higher the HbA1c. The HbA1c test is used to monitor glycemic control in patients with diabetes as well as for the diagnosis of diabetes and categories of increased risk for diabetes.

The DDL, due to its nationally-recognized expertise, also runs the National Glycohemoglobin Standardization Program (NGSP). The NGSP maintains a laboratory network with reference methods that are based on landmark clinical trial data. The program certifies manufacturer methods for HbA1c and also certifies and monitors laboratories doing large studies and clinical trials related to diabetes where measurement of HbA1c is a key variable. Related research includes examination of stability of HbA1c and interferences (especially from Hb variants) with different assay methods.

Standardization of c-peptide is also in progress at the DDL. Assessment of endogenous insulin secretion by measuring C-peptide levels is widely accepted.  Recent studies have shown that preservation of even small amounts of endogenous C-peptide production in patients with Type 1 diabetes reduces risks for diabetic complications.  Standardization of C-peptide results will facilitate comparison of data from different research studies and later among clinical laboratory results at different sites using different assay methods.

A traceability scheme, including a reference method and certified reference materials  has been proposed along with next steps for implementation.  

The standardization process through manufacturer re-calibration is ongoing.

Other research projects include evaluation of glycated albumin for use in patients with renal failure and determination of glycation rates of common variant hemoglobins.


  • Dr. Randie Little
  • Dr. Kuanysh Kabytaev