Skip to main content

Table 2 Positive and negative predictive values of QuantiFERON®-TB Gold results in patients with confirmed TB and patients with other final diagnoses.

From: Use of a T cell interferon gamma release assay in the investigation for suspected active tuberculosis in a low prevalence area

All patients; n = 141     
  Tuberculosis*
n = 70
Other final diagnosis*
n = 71
Positive predictive value Negative predictive value
QFT-G positive 41 16   
QFT-G negative 24 50 71.9% 67.6%
QFT-G indeterminate 5 5   
Suspected pulmonary TB; n = 104     
QFT-G positive 22 14   
QFT-G negative 20 42 61.1% 67.7%
QFT-G indeterminate 2 4   
Suspected extrapulmonary TB; n = 37     
QFT-G positive 19 2   
QFT-G negative 4 8 90.5% 66.7%
QFT-G indeterminate 3 1   
  1. QFT-G: QuantiFERON®-TB Gold; TST: Tuberculin skin test
  2. * Bacteriological and/or clinical diagnosis