Standardization of HbA1c Assays

The Diabetes Control and Complications Trial (DCCT) has demonstrated that HbA1c is an indicator for the development of diabetes [1]. The National Glycohemoglobin Standardization Program (NGSP) has introduced a standardization  based on the DCCT reference method improving the inter-laboratory comparability of HbA1c [2].

The IFCC Working Group on HbA1c Standardization prepared primary reference materials and developed a reference method for HbA1c. According to the consensus agreement of international and national diabetes associations from May 2007 [3], all IVD manufacturers should implement traceability to the IFCC reference system for HbA1c. In future, IFCC results should be reported in mmol/mol (SI unit) and NGSP units in % using the IFCC-NGSP master equation.

[1] N Eng J Med 1993; 329:977 - 86.
[2] Clin Chem 2001; 47:1985 - 92.
[3] Diabetes Care 2007; 30:2399 - 2400.