Figure 4
From: IGRA tests perform similarly to TST but cause no adverse reactions: pediatric experience in Finland
Test parameters of Ly-TbSpot using differential cut-off points (n = 72). Theoretical values for sensitivity (blue), specificity (red), positive (dashed purple) and negative predictive values (dashed grey) on the y-axis were plotted against the cut-off points on the x-axis. The accuracy (black) of the tests peaked to 0.97 in the range of 24 to 48 spots/million lymphocytes. Hence, by preserving our current double cut-off policy (25 and 55 spots/million lymphocytes) we achieve an accuracy of 0.96.