Table 2.
Performance of hemoglobin A1c in the different study cohorts*
| HbA1c cut-off | Sensitivity (%) | Specificity (%) | PPV (%) | NPV (%) |
|---|---|---|---|---|
| Exploration dataset | ||||
| 5.6% (38 mmol/mol) | 87.0 (83.3–90.1) | 57.2 (55.2–59.2) | 25.2 (22.9–27.5) | 96.4 (95.3–97.3) |
| 5.7% (39 mmol/mol) | 83.1 (79.0–86.6) | 66.6 (64.7–68.5) | 29.1 (26.5–31.8) | 96.0 (94.9–96.8) |
| 5.8% (40 mmol/mol) | 76.2 (71.7–80.2) | 74.5 (72.7–76.2) | 33.0 (30.0–36.2) | 95.0 (93.9–95.9) |
| 5.9% (41 mmol/mol) | 71.0 (66.3–75.4) | 81.3 (79.7–82.8) | 38.5 (35.0–42.1) | 94.4 (93.4–95.4) |
| 6.0% (42 mmol/mol) | 66.6 (61.8–71.2) | 85.6 (84.1–86.9) | 43.3 (39.4–47.3) | 93.9 (92.9–94.9) |
| 6.1% (43 mmol/mol) | 60.2 (55.3–65.0) | 90.2 (89.0–91.4) | 50.4 (45.9–54.9) | 93.2 (92.1–94.2) |
| 6.5% (48 mmol/mol) | 44.2 (39.3–49.2) | 98.1 (97.4–98.6) | 78.9 (73.1–84.1) | 91.4 (90.3–92.4) |
|
| ||||
| Internal validation dataset | ||||
| 5.8% (48 mmol/mol) | 76.4 (69.5–82.4) | 75.1 (72.3–77.6) | 34.2 (29.5–39.1) | 94.9 (93.2–96.3) |
|
| ||||
| External validation dataset | ||||
|
| ||||
| 5.8% (48 mmol/mol) | 68.8 (64.1–73.2) | 81.2 (79.4–82.9) | 43.7 (39.9–47.6) | 92.5 (91.1–93.6) |
Data are presented as percentage (95% confidence interval).
*
The Study on Evaluation of iNnovated Screening tools and determInation of optimal diagnostic cut-off points for type 2 diaBetes in Chinese muLti-Ethnic (SENSIBLE) data were split randomly into the exploration dataset (70% of the sample) and the internal validation dataset (the remaining 30%).
Abbreviations: HbA1c, hemoglobin A1c; PPV, positive predictive value; NPV, negative predictive value.