TABLE 3.
MTD cost-effectiveness and one-way sensitivity analysis of variables
| Scenarioc | Marginal MTD cost/patienta | No. of early TB exclusions/100 patientsa | Cost ($)/early exclusion of TB |
|---|---|---|---|
| Base caseb | 338 | 68 | 494 |
| Relative prevalence (%) of TB in smear-positive patients | |||
| 25 | 338 | 75 | 452 |
| 50 | 338 | 50 | 677 |
| 65 | 338 | 35 | 966 |
| 75 | 338 | 25 | 1,355 |
| 90 | 331 | 10 | 3,321 |
| 98.4 | 320 | 2 | 20,087 |
| No. of smear-positive specimens processed by MTD/yr | |||
| 1 | 2,564 | 68 | 3,750 |
| 10 | 407 | 68 | 595 |
| 25 | 260 | 68 | 381 |
| 50 | 208 | 68 | 304 |
| 100 | 176 | 68 | 258 |
| 250 | 141 | 68 | 206 |
| 500 | 114 | 68 | 168 |
| Cost of labor ($/h) | |||
| 15 | 306 | 68 | 448 |
| 35 | 366 | 68 | 535 |
| Marginal cost of reagents ($/test) | |||
| 0 | 144 | 68 | 210 |
| 25 | 346 | 68 | 506 |
| 50 | 548 | 68 | 801 |
| 100 | 952 | 68 | 1,392 |
a
Eligible patients are those with symptoms consistent with TB, no mycobacterial diagnosis or history of treatment in the past 30 days, and at least one AFB-positive smear.
b
Using values from our hospital and from the literature, as described in Table 2.
c
Additionally, we calculated the cost of isolation plus presumptive therapy for a base care ($201), for the case in which the cost of respiratory isolation is $50/day ($334), and for the case in which the time between MTD and culture results is 10 days ($334).