Table I.
Detection of rifampicin (RIF) resistance by Truenat (Truenat Version 1.5) in comparison with comprehensive laboratory reference standards
| Culture | Xpert | Line probe assay | Truenat=1184 | ||
|---|---|---|---|---|---|
| Resistant (R) (%) | Susceptible (S) (%) | Total | |||
| R | R | R | 138 (76.2) | 43 (23.8) | 181 |
| R | R | S | 13 (52) | 12 (48) | 25 |
| R | S | R | 2 (22.2) | 7 (77.8) | 9 |
| R | S | S | 3 (5.6) | 51 (94.4) | 54 |
| S | R | R | 14 (58.3) | 10 (41.7) | 24 |
| S | R | S | 23 (54.8) | 19 (45.2) | 42 |
| S | S | R | 9 (52.9) | 8 (47.1) | 17 |
| S | S | S | 44 (5.3) | 788 (94.7) | 832 |
Truenat MTB/RIF assay in comparison with the pooled cumulative gold standard (rows 1 and 8) yielded sensitivity and specificity of 76.2 and 94.7 per cent, respectively for detection of RIF resistance. Among 54 specimens where both the gold standard molecular tests yielded a susceptible pattern (row 4) Truenat exhibited an agreement of 94.4 per cent. Among 24 specimens where the gold standard molecular tests yielded a resistance pattern (row 5) Truenat exhibited an agreement of 58.3 per cent