Table 5.
Sensitivity, specificity, PPVs and NPVs for different TST cut-offs in correctly identifying IGRA positivity in BCG-vaccinated children
| 5 mm (with 95% CIs) | 10 mm (with 95% CIs) | 15 mm (with 95% CIs) | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Age (years) | Sensitivity | Specificity | PPV | NPV | Sensitivity | Specificity | PPV | NPV | Sensitivity | Specificity | PPV | NPV |
| All children | 94.4 (86.4 to 98.5) | 62.7 (56.1 to 69.0) | 44.4 (36.4 to 52.7) | 97.3 (93.2 to 99.3) | 94.4 (86.4 to 98.5) | 73.7 (67.5 to 79.3) | 53.1 (44.1 to 62.0) | 97.7 (94.2 to 99.4) | 77.8 (66.4 to 86.7) | 84.2 (78.8 to 88.7) | 60.9 (50.1 to 70.9) | 92.3 (87.8 to 95.5) |
| 0 to <2 | 85.7 (42.1 to 99.6) | 52.6 (39.0 to 66.0) | 18.2 (7.0 to 35.5) | 96.8 (83.3 to 99.9) | 85.7 (42.1 to 99.6) | 68.4 (54.8 to 80.1) | 25.0 (9.8 to 46.7) | 97.5 (86.8 to 99.9) | 42.9 (9.9 to 81.6) | 82.5 (70.1 to 91.3) | 23.1 (5.0 to 53.8) | 92.2 (81.1 to 97.8) |
| 2 to <5 | 70.0 (34.8 to 93.3) | 70.9 (57.1 to 82.4) | 30.4 (13.2 to 52.9) | 92.9 (80.5 to 98.5) | 70.0 (34.8 to 93.3) | 76.4 (63.0 to 86.8) | 35.0 (15.4 to 59.2) | 93.3 (81.7 to 98.6) | 70.0 (34.8 to 93.3) | 80.0 (67.0 to 89.6) | 38.9 (17.3 to 64.3) | 93.6 (82.5 to 98.7) |
| 5 to <10 | 100 (89.4 to 100) | 65.3 (53.5 to 76.0) | 55.9 (42.4–68.8) | 100 (92.8 to 100) | 100 (89.4 to 100) | 74.7 (63.3 to 84.0) | 63.5 (49.0 to 76.4) | 100 (93.6 to 100) | 75.8 (57.7 to 88.9) | 86.7 (76.8 to 93.4) | 71.4 (53.7 to 85.4) | 89.0 (79.5 to 95.2) |
| 10 to <15 | 100 (84.6 to 100) | 61.0 (44.5 to 75.8) | 57.9 (40.8–73.7) | 100 (86.3 to 100) | 100 (84.6 to 100) | 75.6 (59.7 to 87.6) | 68.8 (50.0 to 83.9) | 100 (88.8100) | 95.5 (77.2 to 99.9) | 87.8 (73.8 to 95.9) | 80.8 (60.7 to 93.5) | 97.3 (85.8 to 99.9) |
IGRA, interferon γ release assay; NPV, negative predictive value; PPV, positive predictive value; TST, tuberculin skin test.