The impact of alternative assumptions for test properties and latent tuberculosis infection rates (societal perspective)
| Incremental cost-effectiveness ratios (US$ per life year saved) | |||||
|---|---|---|---|---|---|
| No test | TST | IGRA after (+) TST | IGRA after (−) TST | IGRA | |
| 0–2-year-old cohort base-case estimates | 1 * | (Dominated) | (Dominated) | (Dominated) | (Dominated) |
| LTBI rates (%) | |||||
| 8 | 1 * | (Dominated) | (Dominated) | (Dominated) | (Dominated) |
| 48 | 1 * | (Dominated) | (Dominated) | 183812 (QFT), 246342 (TSPOT) | (Dominated) |
| TST sensitivity | |||||
| 75 | 1 * | (Dominated) | (Dominated) | 1532062 † (QFT), 1456062 †(TSPOT) | (Dominated)† |
| 93 | 1 * | (Dominated) | (Dominated) | (Dominated) | (Dominated) |
| TST specificity | |||||
| 62 | 1 * | (Dominated) | (Dominated) | (Dominated)‡ | (Dominated)‡ |
| 88 | 1 * | (Dominated) | (Dominated) | (Dominated) | (Dominated) |
| QFT sensitivity | |||||
| 75 | 1 * | (Dominated) | (Dominated) | (Dominated) | (Dominated) |
| 92 | 1 * | (Dominated) | (Dominated) | (Dominated) | (Dominated) |
| QFT specificity | |||||
| 78 | 1 * | (Dominated) | (Dominated) | (Dominated) | (Dominated) |
| 100 | 1 * | (Dominated) | (Dominated) | (Dominated) | (Dominated) |
| 3–5 year old cohort Base-case estimates | 1 * | (Dominated) | (Dominated) | 2335262 (QFT), 2542432 (TSPOT) | (Dominated) |
| LTBI rates (%) | |||||
| 23 | 1 * | (Dominated) | (Dominated) | (Dominated) | (Dominated) |
| 62 | 1 * | (Dominated) | (Dominated) | 681222 (QFT) 752982 (TSPOT) | (Dominated) |
| TST sensitivity | |||||
| 75 | 1 * | (Dominated) | (Dominated) | 415682 † (QFT), 451562 † (TSPOT) | (Dominated)† |
| 93 | 1 * | (Dominated) | (Dominated) | (Dominated) | (Dominated)† |
| TST specificity | |||||
| 62 | 1 * | (Dominated) | (Dominated) | 6154902 † (QFT), 6782542 †(TSPOT) | (Dominated)† |
| 88 | 1 * | (Dominated) | (Dominated) | 1645502 †(QFT), 1796972 †(TSPOT) | (Dominated)† |
| QFT sensitivity | |||||
| 75 | 1 * | (Dominated) | (Dominated) | 2303352 † (QFT), 252,8602 †(T-SPOT) | (Dominated)† |
| 92 | 1 * | (Dominated) | (Dominated) | 2333262 † (QFT), 2550652 †(TSPOT) | (Dominated)† |
| QFT specificity | |||||
| 78 | 1 * | (Dominated) | (Dominated) | 2320232 † (QFT), 2541562 †(TSPOT) | (Dominated)† |
| 100 | 1 * | (Dominated) | (Dominated) | 2320232 † (QFT), 2541562 †(TSPOT) | (Dominated)† |
↵* The superscript 1 indicates the most cost-effective strategy while 2 indicates a more effective, but less cost-effective strategy. Incremental cost-effectiveness ratios are provided for both types of IGRAs when the no-test strategy does not dominate.
↵† The single IGRA strategy is dominated by the IGRA after negative TST strategy. In all other instances, strategies are dominated by the no-testing strategy.
↵‡ Cost of IGRA after positive TST strategy becomes the most costly strategy. All strategies remain dominated by the no-testing strategy.
IGRA, interferon γ release assay; LTBI, latent tuberculosis infection; QFT, QuantiFERON assay, TSPOT, T-SPOT.TB; TST, tuberculin skin test.