Table 4. Cost and effectiveness of different predictive markers.
| Markers | Cost* (USD) | Cut-off value | Sen. | Spe. | PPV | NPV | LR+ | LR− |
|---|---|---|---|---|---|---|---|---|
| 1st QFT-GIT R | 47.5 | 0.95 IU/ml | 79% | 76% | 78% | 77% | 3.30 (2.18–5.02) | 0.275 (0.18–0.42) |
| 5-factor modelǂ | 53.2 | 0.42 | 84% | 77% | 80% | 80% | 3.56 (2.32–5.46) | 0.22 (0.14–0.36) |
Abbreviations: QFT-GIT R, the response of quantiFERON-TB Gold In-tube; Sen, sensitivity; Spe, specificity; PPV, positive predictive value; NPV, negative predictive value.
*Including assay cost only.
ǂIncludes QFT-GIT response, plasma sTREM-1, history of TB contact, age and currently smoking.
USD is calculated at an exchange rate of 31.6 to NTD on March 16, 2015.