TABLE 3.
Diagnostic properties for the three criteria for interpretation of MRSA screening results
| Test parametera | 30-Day criterion (n = 235)b | Ever-positive criterion (n = 265) | Known-positive criterion (n = 409) |
|---|---|---|---|
| Sensitivity (% [95% CI]) | 79.4 (67.9–88.3) | 85.2 (76.0–91.9) | 70.1 (60.4–78.6) |
| Specificity (% [95% CI]) | 92.8 (87.8–96.2) | 87.6 (81.8–92.0) | 92.7 (89.2–95.4) |
| Positive LR (% [95% CI]) | 12.4 (6.82–23.6) | 7.09 (4.76–11.1) | 10.1 (6.65–15.5) |
| Negative LR (% [95% CI]) | 0.22 (0.12–0.33) | 0.17 (0.08–0.26) | 0.32 (0.23–0.42) |
| MRSA proportion (%) below which NPV is >90% | 33.4 | 39.7 | 34.4 |
| MRSA proportion (%) below which NPV is >95% | 19.2 | 23.8 | 19.9 |
a
LR, likelihood ratio; NPV, negative predictive value.
b
n, number of patients with available results.