Table 2.
Performances of SAT-TB and Bactec MGIT 960 culture methods compared with clinical assessment of patients
| Method and group | Result | No. of cases with clinical diagnosis of TB |
Mean % (95% CI) |
||||
|---|---|---|---|---|---|---|---|
| Positive | Negative | Sensitivity | Specificity | PPV | NPV | ||
| SAT-TB assay | |||||||
| All samples | Positive | 171 | 0 | 67.6 (61.6–73.1) | 100 (97.2–100) | 100 (97.8–100) | 62.0 (55.4–68.3) |
| Negative | 82 | 134 | |||||
| AFB smear-positive group | Positive | 120 | 0 | 97.6 (93.1–99.2) | 100 (34.2–100) | 100 (96.9–100) | 40.0 (11.8–76.9) |
| Negative | 3 | 2 | |||||
| AFB smear-negative group | Positive | 51 | 0 | 39.2 (31.26–47.8) | 100 (97.2–100) | 100 (93.0–100) | 62.6 (55.9–68.8) |
| Negative | 79 | 132 | |||||
| MGIT 960 culture | |||||||
| All samples | Positive | 156 | 0 | 61.7 (55.5–67.43) | 100 (97.2–100) | 100 (97.6–100) | 58.0 (51.6–64.2) |
| Negative | 97 | 134 | |||||
| AFB smear-positive group | Positive | 118 | 0 | 95.9 (90.8–98.3) | 100 (34.2–100) | 100 (96.9–100) | 28.6 (8.2–64.1) |
| Negative | 5 | 2 | |||||
| AFB smear-negative group | Positive | 38 | 0 | 30.2 (22.8–38.7) | 100 (97.2–100) | 100 (90.8–100) | 60.0 (53.4–66.3) |
| Negative | 88 | 132 | |||||