TABLE 1

1997 ADA criteria (4) for IFG, IGT, and diabetes

ConditionFasting plasma glucose (mg/dl)Test and values 2-h OGTT (mg/dl)HbA1c (%)
Normal≤109≤139NA
IFG110–125NANA
IGTNA140–199NA
Diabetes≥126≥200Variable
  • IFG is preferred to IGT by the ADA because of its greater convenience, but IFG and IGT are regarded as equivalent. The ADA recommends against use of HbA1c as a diagnostic test for diabetes. HbA1c threshold for diabetes is variable, but typically between 6.1 and 7.0%. No HbA1c values are recognized as equivalent to IGT or IFG.