Table 3.
Diagnostic sensitivity and specificity for Ig1E to Ara h 2 and IgE to whole peanut extracta
| Test | Cutoff Point | Sensitivity (%) | Specificity (%) | PPV (%) | NPV (%) | Misclassification (%) |
|---|---|---|---|---|---|---|
| IgE to Ara h 2 | 0.30 ISU-E | 99.1 | 91.4 | 95.5 | 98.2 | 3.7 |
| 0.60 ISU-E | 99.1 | 96.6 | 98.1 | 98.3 | 1.8 | |
| 0.65 ISU-E* | 99.1 | 98.3 | 99.1 | 98.3 | 1.2 | |
| 1.0 ISU-E | 97.2 | 98.3 | 99.0 | 95.0 | 2.4 | |
| 2.0 ISU-E | 92.5 | 100.0 | 100.0 | 87.9 | 4.9 | |
| Peanut sIgE | 0.35 kUA/L | 98.1 | 51.7 | 78.8 | 93.8 | 18.3 |
| 2.0 kUA/L | 93.4 | 87.9 | 93.4 | 87.9 | 8.5 | |
| 3.0 kUA/L | 91.5 | 94.8 | 97.0 | 85.9 | 7.3 | |
| 3.5 kUA/L* | 91.5 | 98.3 | 99.0 | 86.4 | 6.1 | |
| 4.0 kUA/L | 90.6 | 98.3 | 99.0 | 85.1 | 6.7 | |
| 5.0 kUA/L | 89.6 | 98.3 | 99.0 | 83.8 | 7.3 | |
| 15.0 kUA/L | 80.2 | 100.0 | 100 | 73.4 | 12.8 |
Sensitivity refers to the propotion of subjects with PA who are correctly identified as having the condition by the test; specificity refers to the proportion of subjects without PA who are correctly identified as not having the condition by the test. PPV: positive predictive value; NPV: negative predictive value.
a
This analysis included 106 peanut-allergic cases and 58 asymptomatic peanut-sensitized children. Two peanut-allergic cases with no available peanut sIgE were removed.
*
optimal cutoff point in this cohort