Results of rifampicin probe compared with phenotypic sensitivity (2003–2009)
| Sample and AFB smear results (2003–2009) | Sensitivity (%) | CI | Specificity (%) | CI | PPV (%) | CI | NPV (%) | CI | Accuracy (%) | CI |
| All* † | 122\132 (92.4) | 86.1 to 96.1 | 2160\2174 (99.4) | 98.9 to 99.6 | 122\136 (89.7) | 83.0 to 94.0 | 2160\2170 (99.5) | 99.1 to 99.8 | 2282\2306 (99.0) | 98.4 to 99.3 |
| All smear +ve | 92\99 (92.9) | 85.5 to 96.9 | 1811\1823 (99.3) | 98.8 to 99.6 | 92\104 (88.5) | 80.3 to 93.6 | 1811\1818 (99.6) | 99.2 to 99.8 | 1903\1922 (99.0) | 98.4 to 99.4 |
| All smear −ve | 21\24 (87.5) | 66.5 to 96.7 | 188\189 (99.5) | 96.6 to 100.0 | 21\22 (95.5) | 75.1 to 99.8 | 188\191 (98.4) | 95.1 to 99.6 | 209\213 (98.1) | 94.9 to 99.4 |
| Respiratory* | 109\116 (94.0) | 64.6 to 90.6 | 1768\1779 (99.4) | 98.8 to 99.6 | 109\120 (90.8) | 57.8 to 84.9 | 1768\1775 (99.6) | 99.1 to 99.8 | 1877\1895 (99.1) | 98.3 to 99.3 |
| Respiratory smear +ve | 52\56 (92.9) | 81.9 to 97.7 | 1554\1559 (99.7) | 99.2 to 99.9 | 52\57 (91.2) | 80.0 to 96.7 | 1554\1558 (99.7) | 99.3 to 99.9 | 1606\1615 (99.4) | 98.9 to 99.7 |
| Respiratory smear −ve | 20\21 (95.2) | 74.1 to 99.8 | 100\100 (100.0) | 95.4 to 100.0 | 20\20 (100.0) | 80.0 to 100.0 | 100\101 (99.0) | 93.8 to 99.9 | 120\121 (99.2) | 94.8 to 100.0 |
| Non- respiratory* | 12\14 (85.7) | 56.2 to 97.5 | 408\410 (99.5) | 98.1 to 99.9 | 12\14 (85.7) | 56.2 to 97.5 | 408\410 (99.5) | 98.1 to 99.9 | 420\424 (99.1) | 97.4 to 99.7 |
| Non- respiratory smear +ve | 8\11 (72.7) | 39.3 to 92.7 | 256\257 (99.6) | 97.5 to 100.0 | 8\9 (88.9) | 50.7 to 99.4 | 256\259 (98.8) | 96.4 to 99.7 | 264\268 (98.5) | 96.0 to 99.5 |
| Non- respiratory smear −ve | 1\3 (33.3) | 1.8 to 87.5 | 169\171 (98.9) | 95.4 to 99.8 | 1\3 (33.3) | 1.8 to 87.5 | 169\171 (98.8) | 95.4 to 99.8 | 170\174 (97.7) | 93.8 to 99.3 |
| Sputum* | 93\101 (92.1) | 84.5 to 96.3 | 1555\1566 (99.3) | 98.7 to 99.6 | 93\104 (89.4) | 81.5 to 94.3 | 1555\1563 (99.5) | 99.0 to 99.8 | 1648\1667 (98.9) | 98.2 to 99.3 |
| Sputum smear +ve | 70\75 (93.3) | 84.5 to 97.5 | 1392\1402 (99.3) | 98.6 to 99.6 | 70\80 (87.5) | 77.8 to 93.5 | 1392\1397 (99.6) | 99.1 to 99.9 | 1462\1477 (99.0) | 98.3 to 99.4 |
| Sputum smear −ve | 16\16 (100.0) | 75.9 to 100.0 | 63\63 (100.0) | 92.8 to 100.0 | 16\16 (100.0) | 75.9 to 100.0 | 63\63 (100.0) | 92.8 to 100.0 | 79\79 (100.0) | 94.2 to 100.0 |