Recommendationsc To avoid misdiagnosis or misseddiagnosis, the A1C test should beperformed using a method that iscertified by the NGSP and standardizedto the Diabetes Control andComplications Trial (DCCT) assay. Bc Marked discordance between measuredA1C and plasma glucoselevels should raise the possibilityof A1C assay interference due tohemoglobin variants (i.e., hemoglobinopathies)and consideration ofusing an assay without interferenceor plasma blood glucose criteria todiagnose diabetes. Bc In conditions associated with increasedred blood cell turnover,such as sickle cell disease, pregnancy(second and third trimesters), hemodialysis,recent blood loss or transfusion,or erythropoietin therapy, onlyplasma blood glucose criteria shouldbe used to diagnose diabetes. B