Table 5.
Association between the exposure variable (age at immigration multiplied by estimated active TB incidence in country of birth) and either test results or latent class status among foreign-born, HIV-seronegative participants aged ≥5 years
| Exposure quartile | TST-positive (RR) | QFT-IT-positive (RR) | TSPOT-positive (RR) | Latent class (RR) |
|---|---|---|---|---|
| 1 | 34.3% (1.0) | 14.9% (1.0) | 13.2% (1.0) | 19.8% (1.0) |
| 2 | 41.9% (1.22) | 22.0% (1.48) | 20.8% (1.58) | 27.0% (1.36) |
| 3 | 53.3% (1.55) | 34.0% (2.28) | 32.5% (2.46) | 39.5% (1.99) |
| 4 | 59.6% (1.74) | 40.2% (2.70) | 41.4% (3.14) | 46.9% (2.37) |
| P value for trend | <2×10−16 | <2×10−16 | <2×10−16 | <2×10−16 |
QFT-IT, QuantiFERON Gold In-Tube; RR, relative risk; TSPOT, T-SPOT.TB, classified as positive/negative by using the international standard (≥6 spots=positive; TST, tuberculin skin test; ≤5 spots=negative).