From: Using IFN-gamma release assay to confirm tuberculin skin test improves the screening of latent tuberculosis infection in Italian healthcare workers
IGRA
p-value
Negative
Positive
n.
%
TST diameter (n.)
0–9 (29)
29
100.0
-
0.001
10–15 (75)
57
76.0
18
24.0
> 15 (51)
37
72.5
14
27.5