TABLE 1.
Performance of pooled processed DNA compared to that of individually tested samples
| Bacterium | No. of pools tested | Total no. (%) of presumptive positives in the pool | No. of positive pools with positive individual results (% true positives) | No. of positive pools with negative individual results (% false positives) | No. of negative pools with negative individual results (% true negatives) | No. of negative pools with positive individual results (% false negatives) | Specificity of pool (%) | Sensitivity of pool (%) | PPVa (%) | NPVb (%) |
|---|---|---|---|---|---|---|---|---|---|---|
| S. pneumoniae | 119 | 82 (69) | 78 (65) | 4 (3) | 33 (28) | 4 (3) | 89 | 95 | 95 | 89 |
| H. influenzae | 119 | 63 (53) | 60 (50) | 3 (2) | 55 (46) | 1 (1) | 95 | 98 | 95 | 98 |
| K. pneumoniae | 119 | 63 (53) | 46 (39) | 17 (14) | 54 (45) | 2 (2) | 76 | 96 | 73 | 96 |
| Total | 357 | 208 (58) | 184 (52) | 24 (7) | 142 (40) | 7 (2) | 86 | 96 | 88 | 95 |
a
PPV, positive predictive value.
b
NPV, negative predictive value.