Characteristics of 34 cross-sectional IGRA studies in HCWs
| Study | Year | Country | N | TST (PPD dose) | IGRA (QFT, TSPOT.TB or both) | BCG vaccinated (%) |
| High TB incidence countries | ||||||
| Pai et al22 | 2005 | India | 726 | 1 TU | QFT-G-IT | 71 |
| Drobniewski et al23 | 2007 | Russia | 500 | – | QFT-G-IT | 84 |
| Lien et al24 | 2009 | Vietnam | 300 | 5 TU | QFT-G-IT | 37.3 |
| Intermediate and low TB incidence countries | ||||||
| Kang et al25 | 2005 | Republic of Korea | 171 | 2 TU | QFT | 92.3 |
| Harada et al26 | 2006 | Japan | 332 | 2.5 TU | QFT-G | 91.3 |
| Ozekinci et al27 | 2007 | Turkey | 66 | 5 IU | T-SPOT.TB | 67 |
| Veeser et al28 | 2007 | USA | 55 | – | QFT-G | 45 |
| Soborg et al29 | 2007 | Denmark | 139 | 2 TU | QFT-G | 76 |
| Nienhaus et al30 | 2007 | Germany | 454 | – | QFT-G-IT | 42 |
| Nienhaus et al31 | 2007 | Germany | 161 | 2 TU | QFT-G-IT | 36 |
| Mirtskhulava et al32 | 2008 | Georgia | 265 | 5 TU | QFT-G-IT | 77.7 |
| Hotta et al33 | 2007 | Japan | 207 | 3 TU | QFT-TB-2G | 92% (48% with >1 BCG) |
| Nienhaus et al34 | 2008 | Germany | 261 | 2 TU | QFT-G-IT | 37.5 |
| Ciaschetti et al35 | 2007 | Italy | 590 | – | QFT-G | 56 |
| Eum et al36 | 2008 | Republic of Korea | 73 | – | QFT-GIT | 100 |
| Choi et al37 | 2008 | Republic of Korea | 84 | 2 TU | QFT-G | 100 |
| Carvalho et al38 | 2008 | Italy | 65 | 5 IU | QFT-G | 85 |
| Barsegian et al39 | 2008 | Germany | 95 | – | T-SPOT.TB | 36 |
| Stebler et al40 | 2008 | Switzerland | 777 | – | QFT-G-IT | 87.4 |
| Thijsen et al41 | 2008 | The Netherlands | 19* | – | QFT-G-IT and T-SPOT.TB | 16 |
| Demkow et al42 | 2008 | Poland | 155 | – | QFT-G | 100 |
| Schablon et al43 | 2009 | Germany | 270 | – | QFT-G-IT | 52.8 |
| Dorman et al44 | 2009 | USA | 1313 | – | QFT-G-IT and T-SPOT.TB | – |
| Mehta et al45 | 2009 | USA | 12† | QFT-G | – | |
| Vinton et al46 | 2009 | Australia | 481 | 10 IU | QFT-G-IT | 78 |
| Zrinski Topić et al47 | 2009 | Croatia | 54 | 2 TU | QFT-G-IT | 100 |
| Khanna et al48 | 2009 | UK | 171 | 2 TU | QFT-G-IT | 82.5 |
| Álvarez-León et al49 | 2009 | Spain | 134 | 2 TU | QFT-G-IT | 35 |
| Casas et al50 | 2009 | Spain | 147 | 2 TU | T-SPOT.TB & QFT-G-IT | 16 |
| Fox et al51 | 2009 | Israel | 100 | 5 PPD | QFT-G-IT | 37 |
| Costa et al52 53 * | 2009 | Portugal | 1218 | 2 TU | QFT-G-IT | 100 |
| Zhao et al54 | 2009 | USA | 40 | – | QFT-G-IT | – |
| Girardi et al55 | 2009 | Italy | 115 | 5 IU | T-SPOT.TB and QFT-G-IT | 37.4 |
| Cummings et al56 | 2009 | USA | 182 | – | QFT-G-IT | 7 |
↵* Two studies based on same cohort, ERJ data displayed in table.
↵† All subjects were TST converters at recruitment.
BCG, Bacille Calmette-Guerin vaccine; HCW, healthcare worker; IGRA, interferon-gamma release assay; IU, international unit; PPD, purified protein derivative; QFT, QuantiFERON test; QFT-G, QFT Gold test; QFT-G-IT; QFT Gold In-Tube test; TB, tuberculosis; TST, tuberculin skin test; TU, tuberculin unit.