Table 2 Performance Characteristics of Xpert on sediments and raw sputum samples
Performance characteristics of Xpert in Presumptive PTB using LJ culture as a reference method (N = 262) | ||||
Sensitivity (%) | Specificity (%) | PPV (%) | NPV (%) | P-value |
Performance characteristics of Xpert on sputum sediments using experimental dilution (1:2) | ||||
92 (84–97) | 85 (79–90) | 74 (67–80) | 96 (91–98) | 0.0001 |
Performance characteristics of Xpert on raw sputa using standard dilution (1:2) | ||||
86 (77–93) | 86 (77–93) | 75 (65–83) | 93 (88–96) | 0.001 |
Incremental values | ||||
6 | 1 | 1 | 3 | |
Performance characteristics of Xpert in HIV Infected presumptive PTB (n = 39) | ||||
Performance characteristics of Xpert on sputum sediments using experimental dilution (1:2) | ||||
100 (81–100) | 82 (60–95) | 81 (64–91) | 100 | 0.0001 |
Performance characteristics of Xpert on raw sputa using standard dilution (1:2) | ||||
88 (64–99) | 86 (65–97) | 83 (59–96) | 91 (70–99) | 0.0001 |
Incremental values | ||||
12 | 4 | 2 | 9 | |