Table 4.
Cost-effectiveness of six TB screening strategies for a cohort of 1000 healthcare workers over 20 years: base-case scenario
| Strategy | Cost in 2015 $Can | Incremental cost | QALYs | Increment in QALYs | Incremental cost per QALY gaineda | New active TB cases | Increment in active TB cases prevented | Incremental cost per additional TB case preventeda |
|---|---|---|---|---|---|---|---|---|
| Post-exposure screening only | ||||||||
| Tuberculin Skin Test | $66,387 | — | 15,239.98 | –– | –– | 3.03 | — | — |
| QuantiFERON®-TB-Gold | $77,521 | $11,134 | 15,239.85 | –0.13 | –– (Dominatedb) | 2.97 | 0.06 | $197,017 |
| Targeted screening | ||||||||
| Tuberculin Skin Test | $151,517 | $85,130 | 15,237.96 | –2.02 | –– (Dominatedb) | 2.83 | 0.14 | $517,437c |
| QuantiFERON®-TB-Gold | $263,660 | $197,273 | 15,236.90 | –3.07 | –– (Dominatedb) | 2.86 | –0.04 | — (Dominatedb) |
| Annual screening | ||||||||
| Tuberculin Skin Test | $404,956 | $338,569 | 15,231.85 | –8.12 | –– (Dominatedb) | 2.68 | 0.15 | $1,717,539 |
| QuantiFERON®-TB-Gold | $817,695 | $751,308 | 15,227.92 | –12.06 | –– (Dominatedb) | 2.80 | –0.12 | — (Dominatedb) |
TB tuberculosis, QALYs quality-adjusted life years
aRelative to next most expensive, non-dominated strategy
bDominated because it is more expensive and less effective than the proposed alternative; hence no incremental cost-effectiveness ratios are provided
cIncremental cost of $426,678 per additional TB case prevented, relative to post-exposure TST screening only