Divergence factor in HbAlc measurement with domestic and/or international standard material - Divergence factor between POCT HbAlc measurement DCA2000/DCA vantage and the domestic daily method used in Japan

We investigated the divergence factor between HbAlc measurement using DCA2000/Vantage (DCA) and the domestic daily method used in Japan referencing the KO 500 method, i.e., JSCC/JDS standard measurement. Calibration settings of the international standardization material and of DCA internal calibration material mostly resembled DCA measurement but measured 7 % to 10 % lower in relative percentage than the KO 500 method setting. KO500 chromatography recognized the peak of foreign substances not recognized by JDS Lot 4 in calibration of the international standardization material or of the DCA internal calibration material. The DCA divergence factor was thought to be caused by a difference in standard material composition or a difference in operation method separation capability. DCA showed a valid result by adopting calibration decided by the Japan Diabetes Society (JDS) and supplied the product based on JDS Lot 4 from July 2010.