Table 4.

Performance of A1c in the screening for a diabetic 2h-PG (≥200 mg/dl)

A1c (%)Diabetes Identified (n = 41)OGTTs Required (%)Sensitivity (95% CI)Specificity (95% CI)
≥5.039432 (86)0.95 (0.84 to 0.99)0.15 (0.12 to 0.18)
≥5.133407 (81)0.81 (0.66 to 0.90)0.19 (0.16 to 0.23)
≥5.233382 (76)0.81 (0.66 to 0.90)0.25 (0.21 to 0.29)
≥5.330351 (70)0.73 (0.58 to 0.84)0.31 (0.27 to 0.35)
≥5.430316 (63)0.73 (0.58 to 0.84)0.38 (0.33 to 0.42)
≥5.528286 (57)0.68 (0.53 to 0.80)0.44 (0.40 to 0.49)
≥5.622236 (47)0.54 (0.39 to 0.68)0.54 (0.49 to 0.59)
  • ROC analyses in patients with FPG <126 mg/dl and available A1c data (n = 502 of 514 patients with A1c data). The ROC AUC value is 0.578 (95% CI 0.482 to 0.673).