TABLE 2.

Performance of Xpert MTB/RIF assay

Sample originSmear sample typeXpert MTB resultDetection in solid medium cultureDetection in liquid medium cultureDetection in liquid and solid medium cultureSpecificitya (95% CI)
No. of samples by culture typeSensitivity (95% CI)No. of samples by culture typeSensitivity (95% CI)No. of samples by culture typeSensitivity (95% CI)
+++
VietnamPositive+290100 (85.4-100)290100 (85.4-100)290100 (85.4-100)
000000
Negative+33084.6 (68.8-93.6)37071.1 (56.7-82.4)38071.7 (57.4-82.8)100 (83.4-100)
62515251525
UgandaPositive+63098.4 (90.5-99.9)63098.4 (90.5-99.9)63098.4 (90.5-99.9)100 (80.0-100)
120120120
  • a Specificity values represent the proportions of culture-negative samples that were correctly identified as giving negative results by the Xpert MTB/RIF assay.