AUC, NRI and IDI results with culture-confirmed TB and empirical treatment for active TB as the outcome in smear-negative children (n=491). Comparisons are made between the baseline model with clinical predictors, CXR and TST and the expanded model with addition of T-SPOT.TB
| AUC expanded (95% CI) | AUC baseline (95% CI) | AUC difference (95% CI) | NRI events (95% CI) | NRI non-events (95%CI) | NRI sum (95% CI) | IDI events (95% CI) | IDI non-events (95% CI) | IDI sum (95% CI) | |
|---|---|---|---|---|---|---|---|---|---|
| Culture-confirmed TB | |||||||||
| Clinical+CXR+TST+T-SPOT.TB (binary) | 0.88 (0.85 to 0.92) | 0.85 (0.80 to 0.90) | 0.03 (0.002 to 0.07) | 0.03 (−0.10 to 0.28) | 0.04 (−0.01 to 0.07) | 0.07 (−0.08 to 0.31) | 0.02 (0.001 to 0.10) | 0.01 (0.001 to 0.01) | 0.03 (0.001 to 0.11) |
| Clinical+CXR+TST+T-SPOT.TB (quantitative) | 0.87 (0.84 to 0.92) | 0.85 (0.80 to 0.90) | 0.02 (0.002 to 0.06) | 0.07 (−0.09 to 0.22) | 0.01 (−0.01 to 0.07) | 0.08 (−0.07 to 0.25) | 0.04 (0.002 to 0.10) | 0.004 (0.001 to 0.01) | 0.04 (0.002 to 0.12) |
| Empirical treatment for active TB | |||||||||
| Clinical+CXR+TST+T-SPOT.TB (binary) | 0.86 (0.83 to 0.90) | 0.84 (0.81 to 0.88) | 0.02 (0.003 to 0.03) | 0.01 (−0.02 to 0.04) | 0.12 (−0.01 to 0.19) | 0.13 (−0.001 to 0.20) | 0.01 (0.002 to 0.03) | 0.01 (0.003 to 0.03) | 0.02 (0.01 to 0.06) |
| Clinical+CXR+TST+T-SPOT.TB (quantitative) | 0.86 (0.83 to 0.90) | 0.84 (0.81 to 0.88) | 0.02 (0.003 to 0.04) | 0.01 (−0.03 to 0.05) | 0.08 (−0.01 to 0.22) | 0.09 (−0.01 to 0.24) | 0.01 (0.003 to 0.03) | 0.02 (0.003 to 0.03) | 0.03 (0.01 to 0.06) |
AUC, area under the curve; CXR, chest radiography; IDI, integrated discrimination improvement; NRI, net reclassification improvement; TST, tuberculin skin test.