TABLE 1.
Comparison of various methods for the detection of GBS
| Test (reference) | Sensitivity (%) | Specificity (%) | PPVa (%) | NPVb (%) |
|---|---|---|---|---|
| Culture | ||||
| Routine culture (6) | 42.3 | 100 | 100 | 74.3 |
| Routine culture (3) | 54.3 | 97.1 | 79.7 | 91.1 |
| Routine culture (this study) | 68.4 | 100 | 100 | 87.9 |
| Selective Strep (this study) | 85.5 | 100 | 100 | 94.1 |
| Antigen detection, PathoDx (6) | 57.3 | 99.5 | 98.5 | 79.5 |
| Molecular methods | ||||
| cfb gene (6) | 75.3 | 100 | 100 | 87.1 |
| GBS AccuProbe assay (15) | 90.1 | 97.5 | 91.1 | 97.2 |
| GBS LightCycler assay with MagNA Pure Compact (12) | 92.5 | 99.1 | 97.4 | 97.5 |
| IDI-Strep B assay (3) | 94.0 | 95.9 | 83.8 | 98.6 |
| PCR for scpB gene (6) | 99.6 | 100 | 100 | 99.7 |
| GBS LightCycler assay with MagNA Pure LC (12) | 100 | 96.9 | 88.6 | 100 |
| GBS PNA FISH assay (this study) | 97.4 | 98.3 | 96.1 | 98.9 |
a
PPV, positive predictive value.
b
NPV, negative predictive value.