TABLE 1.
Characteristics of study population
| Characteristic | Recruits (n = 17) | Individuals in after deployment/other risk factors group (n = 175) | P value |
|---|---|---|---|
| Mean ± SD age (yr) | 23.0 ± 4.1 | 29.7 ± 9.6 | 0.001 |
| No. (%) of participants | |||
| Female sex | 4 (23.5) | 10 (5.7) | 0.007 |
| Foreign born | 0 | 8 (4.6) | 0.37 |
| Travel to tropics | 5 (29.4) | 30 (17.1) | 0.21 |
| Reported contact with TB | 3 (17.6) | 19 (10.9) | 0.4 |
| Mean ± SD TST result (mm) | 15.9 ± 2.9 | 13.3 ± 2.8 | <0.001 |
| TST category | |||
| 10-14 mm | 4 (23.5) | 132 (75.4) | <0.001 |
| 15-19 mm | 11 (64.7) | 35 (20.0) | |
| ≥ 20 mm | 2 (11.8) | 8 (4.6) | |
| Mean ± SD no. of QFT-Git performed | 2.8 ± 1.1 | 3.3 ± 0.9 | 0.065 |
| Initial no. (%) of participants QFT-Git positive | 7 (41.2) | 12a (6.9) | <0.001 |
| No. (%) of participants with QFT-Git follow-up patternb: | <0.001 | ||
| Consistent negative | 8 (53.4) | 155 (92.3) | |
| Conversion | 1 (6.7) | 1 (0.6) | |
| Consistent positive | 5 (33.3) | 4 (2.4) | |
| Reversion | 1 (6.7) | 8 (4.8) |
a
Denominator was 174 due to one missing sample; all 12 positive results were in personnel returned from deployment abroad.
b
For definitions, see Materials and Methods.