Table 1.
A comparison of the relative transmission rate and proportion of transmissionsa attributable to smear-negative sources when replicating previous methodology versus our combined approach.
| Relative Transmission Rate | Proportion of Transmissions Attributable to Smear-Negative Source | |
|---|---|---|
| Replication of DNA fingerprint clustering methods (Method #1) | 0.19 (95% CI, 0.14–0.26) | 16% (95% CI, 12–19%) |
| Molecular and conventional epidemiology supplemented with whole genome sequencing (Method #2) | 0.10 (95% CI, 0.05–0.19) | 8% (95% CI, 3–14%) |
| Sensitivity analysis #1 (attributed transmission to a smear-negative case even if the secondary case had also been exposed to a smear-positive individual) | 0.13 (95% CI, 0.07–0.24) | 11% (95% CI, 5–17%) |
| Sensitivity analysis #2 (excluded contacts who had only been in Canada less than 180 days) | 0.08 (95% CI, 0.04–0.17) | 7% (95% CI, 2–12%) |
| Behr et al. 1999 | 0.22 | 17% |
| Tostmann et al. 2008 | 0.24 | 13% |
| Hernandez-Garduno et al. 2004 | n/a | 17–41% |
a
Test comparing Method #1 vs Method #2, p = 0.048. Global test comparing Method #1 vs Method #2 vs Sensitivity analysis #1 vs Sensitivity analysis #2, p = 0.038.