Table 1 Latex agglutination test results as compared with different density levels of GBS for 100 culture-positive specimens
Density level of GBS (c.f.u. per swab) | No. of samples tested positive (n) | No. of samples positive for GBS (n) | Sensitivity (%) | Specificity (%) | PPV (%) | NPV (%) |
|---|---|---|---|---|---|---|
High (>100) | 22 | 22 | 22/22 (100 %) | 22/22 (100 %) | 22/22 (100 %) | 22/22 (100 %) |
Moderate (50–100) | 27 | 27 | 27/27 (100 %) | 27/27 (100 %) | 27/27 (100 %) | 27/27 (100 %) |
Low (10–50) | 24 | 36 | 24/36 (66.7 %) | 36/36 (100 %) | 24/24 (100 %) | 36/48 (75.0 %) |
Little (<10) | 2 | 15 | 2/15 (13.3 %) | 15/15 (100 %) | 2/2 (100 %) | 15/28 (53.6 %) |