Table 4

Different approaches to routine screening with tuberculin skin test and QuantiFERON®TB Gold

Screening programme approach
Referral criteria
Proportion (%) referred for treatment
Proportion (%) LTBI* cases detected (detection rate)
Proportion (%) non-infected referred for treatment (false positive rate)

Only TST
TST ≥ 6 mm
50
89
42

TST ≥ 10 mm
34
75
27

TST ≥ 15 mm
15
47
0
Only QFT
QFT positive
29
88
0
Two step (first TST, then QFT)
TST ≥ 6 mm and QFT positive, or TST ≥15 mm
29
89
0

TST ≥ 10 mm and QFT positive or TST ≥ 15 mm
25
75
0

TST ≥ 15 mm (with or without QFT positives afterwards)
15
47
0

*Latent infection is defined as either having a positive QuantiFERON(R)TB Gold test (264 participants) or a tuberculin skin test ≥15 mm and a negative QuantiFERON(R)TB Gold test (37 participants). Effect on screening based on identification of 301 cases of latent tuberculosis infection among 912 newly arrived asylum seekers in Norway Sept. 19. 2005 – June 12.2006

Winje et al. BMC Infectious Diseases 2008 8:65   doi:10.1186/1471-2334-8-65