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Table 4 Diagnostic performance of TB-LAMP, smear microscopy and Xpert MTB/Rif test in pulmonary TB

From: Performance of loop-mediated isothermal amplification assay in the diagnosis of pulmonary tuberculosis in a high prevalence TB/HIV rural setting in Uganda

Diagnostic performance measure Tests performance with LJ and /or MGIT MTB culture as reference standard
TB-LAMP performance (95% CI) FM/ZN performance (95% CI) Xpert MTB/Rif test performance (95% CI)
Sensitivity 46/83, 55.4 (44.1-66.3) 38/83, 45.8 (34.8-57.1) 54/83, 65.1 (53.8-75.2)
Specificity 147/150, 98.0 (94.3-99.6) 145/150, 96.7 (92.4-98.9) 138/150, 92.0 (86.4-95.8)
PPV 46/49, 93.9 (83.1-98.7) 38/43, 88.4 (74.9-96.1) 54/66, 81.8 (70.4-90.2)
NPV 147/184, 79.9 (73.4-85.4) 145/190, 76.3 (69.6- 82.2) 138/167, 82.6% (76.0-88.1)
LR (positive) 27.7 (8.9-86.4) 13.7 (5.62-33.6) 8.13 (4.62-14.31)
LR (negative) 0.45 (0.36-0.58) 0.60 (0.46-0.77) 0.38 (0.28-0.51)
  1. PPV Positive predictive value, NPV Negative predictive value, LR Likelihood ratio, CI Confidence intervals, FM fluorescence microscopy, ZN Ziehl-Neelson, MGIT mycobacterial growth indicator tube, LJ Lowenstein-Jensen