Table 3

Test performance estimated from area under the ROC curves using 2-hour OGTT and fasting plasma glucose values as reference test according to the WHO and NICE diagnostic criteria

Reference criteriaTest assessedAUC‡95% CIP values§
2-hour OGTT ≥8.5 mmol/L*1-hour OGTT0.880.81 to 0.94<0.0001
Fasting glucose0.860.80 to 0.91<0.0001
Random glucose0.600.51 to 0.690.035
HbA1c0.480.40 to 0.570.686
2-hour OGTT ≥7.8 mmol/L†1-hour OGTT0.850.80 to 0.91<0.0001
Fasting glucose0.830.78 to 0.88<0.0001
Random glucose0.620.55 to 0.690.002
HbA1c0.480.40 to 0.550.567
Fasting glucose ≥5.1 mmol/L*1-hour OGTT0.770.71 to 0.82<0.0001
2-hour OGTT0.780.72 to 0.83<0.0001
Random glucose0.630.57 to 0.69<0.0001
HbA1c0.510.44 to 0.570.880
Fasting glucose ≥5.6 mmol/L†1-hour OGTT0.760.68 to 0.84<0.0001
2-hour OGTT0.780.70 to 0.86<0.0001
Random glucose0.650.56 to 0.740.001
HbA1c0.510.41 to 0.600.867
  • *WHO and †NICE diagnostic criteria. ‡Area under the curve under the null hypothesis=0.5. Test rated excellent for AUC 0.9–1.0, very good for AUC 0.8–0.9, good for AUC 0.70–0.80, sufficient for AUC 0.60–0.70, poor for AUC 0.50–0.60 and invaluable for AUC <0.5 if p<0.05.23 24 §The lower the p value, the higher the clinical relevance of the test.

  • HbA1c, glycated hemoglobin; NICE, National Institutefor Health and Care Excellence; OGTT, oral glucose tolerance test; ROC, receiver operating characteristic.