TABLE 3.
Comparison of the Characteristics of Increased Risk Healthcare Workers (HCWs) Who Tested Negative With the QuantiFERON-TB Gold (QFT-G) Assay and Those Who Tested Positive With QFT-G
| Characteristic | QFT-G negative | QFT-G positivea | P |
|---|---|---|---|
| TST induration, mm, mean ± SD | 16.3 ± 3.2 | 17.4 ± 3.9 | .28 |
| Age, years, mean ± SD | 35.8 ± 8.4 | 38.9 ± 9.4 | .20 |
| Recent immigration (within ≤5 years) from high-risk area | 7/43 (16) | 8/22 (36) | .069 |
| ≥5 years of residence in an area highly endemic for TB | 29/43 (67) | 20/22 (91) | .038 |
| Self-reported history of BCG vaccination | 43/43 (100) | 21/23 (91) | Not done |
| Casual or close contact with TB patient | 32/43 (74) | 12/22 (55) | .105 |
| Female | 27/43 (63) | 13/23 (57) | Not done |
NOTE. Data are proportion (%) of HCWs, unless otherwise indicated. BCG, bacille Calmette-Guérin; SD, standard deviation; TB, tuberculosis; TST, tuberculin skin test.
a
Data on immigration, residency, and TB contact were not available for 1 of the 23 HCWs who tested positive. For definitions of “high-risk area” and “casual or close contact with TB patient,” see Methods.