Table 2.
Correlation between slime formation (Congo red agar screening) and development of biofilm biomass (crystal violet staining).
| Glucose | Sensitivity | Specificity | PPV | NPV | CRA+/CV+ | CRA-/CV+ | CRA+/CV- | CRA-/CV- |
|---|---|---|---|---|---|---|---|---|
| (%) | (%) | (%) | (%) | (%) | Number of S. aureus strains | |||
| 0 | 6.3 | 91.0 | 5.0 | 92.8 | 1 | 15 | 19 | 193 |
| 0.1 | 9.7 | 91.3 | 15.0 | 86.5 | 3 | 28 | 17 | 180 |
| 0.25 | 11.6 | 93.0 | 45.0 | 63.5 | 11 | 76 | 9 | 132 |
| 0.5 | 8.3 | 80.0 | 90.0 | 3.9 | 18 | 200 | 2 | 8 |
(PPV) positive predictive value (NPV) negative predictive value (CRA) Congo red agar screening (CV) crystal violet staining