Reliability of different potential definitions of diabetes, using HbA1c ≥6.5% as the gold standard
| Potential definition | Patients meeting criteria (%)* | Sensitivity (%) | Specificity (%) | PPV (%) | NPV (%) | Accuracy† (%) |
|---|---|---|---|---|---|---|
| (A) RPG >140 mg/dL | 33.8 | 70.9 | 74.3 | 37.6 | 92.1 | 73.7 |
| (B) RPG >180 mg/dL | 14.3 | 50.4 | 93.6 | 63.1 | 89.6 | 85.8 |
| (C) RPG ≥200 mg/dL | 10.8 | 43.6 | 96.4 | 72.4 | 88.7 | 86.9 |
| (D) ≥1 FPG levels ≥126 mg/dL | 36.2 | 78.4 | 73.0 | 38.8 | 93.9 | 74.0 |
| (E) ≥2 FPG levels ≥126 mg/dL | 17.0 | 58.9 | 92.2 | 62.2 | 91.1 | 86.2 |
| (F) ≥1 FPG levels >140 mg/dL | 23.1 | 67.0 | 86.5 | 51.9 | 92.3 | 83.0 |
| (G) ≥2 FPG levels >140 mg/dL | 10.0 | 42.2 | 97.1 | 75.8 | 88.5 | 87.2 |
| (H) ≥1 FPG ≥126 and RPG (I) ≥200 mg/dL | 8.6 | 40.4 | 98.4 | 84.4 | 88.3 | 88.0 |
| (J) ≥1 FPG >140 and RPG (K) ≥200 mg/dL | 7.7 | 37.9 | 98.9 | 88.4 | 88.0 | 88.0 |
*Prevalence of diabetes per HbA1c screening=17.9%.
†Accuracy=% of true results (ie, (true positives+true negatives)/total).
FPG, fasting plasma glucose; HbA1c, glycosylated hemoglobin; NPV, negative-predictive value; PPV, positive-predictive value; RPG, random plasma glucose (collected at admission).