Table 1. Baseline characteristics of the enrolled population and the comparisons between QFT positive and QFT negative populations.
| Characteristics | Total | QFT Negative | QFT Positive | OR | P Value | |||
|---|---|---|---|---|---|---|---|---|
| Age (years) | n | % | n | % | n | % | ||
| 5–9 | 98 | 1.8 | 96 | 2.3 | 2 | 0.2 | reference | |
| 10–19 | 295 | 5.6 | 291 | 6.9 | 4 | 0.4 | 0.66(0.12–3.66) | 0.6346 |
| 20–29 | 397 | 7.5 | 374 | 8.8 | 23 | 2.2 | 2.95(0.68–12.74) | 0.1468 |
| 30–39 | 463 | 8.7 | 407 | 9.6 | 56 | 5.3 | 6.60(1.58–27.54) | 0.0096 |
| 40–49 | 1293 | 24.4 | 1073 | 25.3 | 220 | 20.8 | 9.84(2.41–40.22) | 0.0015 |
| 50–59 | 1136 | 21.4 | 840 | 19.8 | 296 | 27.9 | 16.91(4.14–69.04) | <0.0001 |
| 60–69 | 1030 | 19.4 | 751 | 17.7 | 279 | 26.3 | 17.83(4.37–72.82) | <0.0001 |
| ≥70 | 593 | 11.2 | 413 | 9.7 | 180 | 17.0 | 20.92(5.10–85.78) | <0.0001 |
| Gender | ||||||||
| Female | 2838 | 53.5 | 2360 | 55.6 | 478 | 45.1 | reference | <0.0001 |
| Male | 2467 | 46.5 | 1885 | 44.4 | 582 | 54.9 | 1.52(1.33–1.75) | |
| Education | ||||||||
| Primary school or lower | 2356 | 44.4 | 1799 | 42.4 | 557 | 52.5 | reference | |
| Middle school | 2090 | 39.4 | 1709 | 40.3 | 381 | 35.9 | 0.72(0.62–0.83) | <0.0001 |
| High school | 671 | 12.6 | 558 | 13.1 | 113 | 10.7 | 0.65(0.52–0.82) | 0.0002 |
| College or higher | 188 | 3.5 | 179 | 4.2 | 9 | 0.8 | 0.16(0.08–0.32) | <0.0001 |
| Smoking | ||||||||
| Never smoked | 4013 | 75.6 | 3320 | 78.2 | 693 | 65.4 | reference | <0.001 |
| Ever smoked | 1292 | 24.4 | 925 | 21.8 | 367 | 34.6 | 1.83(1.59–2.10) | |
| Alcohol drinking | ||||||||
| No | 4119 | 77.6 | 3377 | 79.6 | 742 | 70.0 | reference | <0.001 |
| Yes | 1186 | 22.4 | 868 | 20.4 | 318 | 30.0 | 1.67(1.43–1.94) | |
| BMI (Kg/m2) | ||||||||
| <18.5 | 330 | 6.2 | 289 | 6.8 | 41 | 3.9 | 0.65(0.46–0.92) | 0.0139 |
| ≥18.5 and <23 | 2184 | 41.2 | 1792 | 42.2 | 392 | 37.0 | reference | |
| ≥23 and <27.5 | 2222 | 41.9 | 1714 | 40.4 | 508 | 47.9 | 1.36(1.17–1.57) | <.0001 |
| ≥27.5 | 569 | 10.7 | 450 | 10.6 | 119 | 11.2 | 1.21(0.96–1.52) | 0.1055 |
| Family history of TB | ||||||||
| No | 5232 | 98.6 | 4192 | 98.8 | 1040 | 98.1 | reference | 0.1126 |
| Yes | 73 | 1.4 | 53 | 1.2 | 20 | 1.9 | 1.52(0.91–2.56) | |
| Close contact with TB patients | ||||||||
| No | 5270 | 99.3 | 4223 | 99.5 | 1047 | 98.8 | reference | 0.0135 |
| Yes | 35 | 0.7 | 22 | 0.5 | 13 | 1.2 | 2.38(1.20–4.75) | |
| BCG Scar | ||||||||
| No | 3410 | 64.3 | 2567 | 60.5 | 843 | 79.5 | reference | <.0001 |
| Yes | 1895 | 35.7 | 1678 | 39.5 | 217 | 20.5 | 0.39(0.34–0.46) |
Abbreviations: BCG, bacillus Calmette-Guérin; BMI, body mass index; CI, confidence interval; QFT, QuantiFERON-TB Gold In-TubeQFT; OR, odds ratio; TB, tuberculosis.