Table 4

A comparison of the T-SPOT.TB and QFT-GIT assays where both tests were undertaken

T-SPOT.TB positive316037 (8.1%)*
T-SPOT.TB negative928962360 (78%)
T-SPOT.TB inconclusive3+243+68+062 (14%)
  • Comparisons are based on the McNemar test for paired proportions.

  • A T-SPOT.TB result was inconclusive if the test was not completed or the result was indeterminate.

  • * Proportions positive: 9% (of completed T-SPOT.TB) and 8% (of attempted T-SPOT.TB) vs 10% (QFT-GIT), p=0.3 and p=0.1, respectively.

  • x+y: T-SPOT.TB number not completed+number indeterminate;

  • Proportions indeterminate: 2% (T-SPOT.TB) vs 15% (QFT-GIT), p<0.0001. Proportions inconclusive (not completed or indeterminate): 14% (T-SPOT.TB) vs 15% (QFT-GIT), p=0.5.