Table 3 Sensitivity and specificity of cumulative anti‐P aeruginosa antibody scores according to the method by which material was obtained for microbiological culture.
| Sputum only | All (sputum + swab) | Swab only | |
|---|---|---|---|
| Number of subjects (n) | 76 | 183 | 107 |
| Sensitivity % (95% CI) | 95.4 (87.1 to 99.0) | 86.1 (78.4 to 91.8) | 74.0 (59.7 to 85.4) |
| (n/N) | 62/65 | 99/115 | 37/50 |
| Specificity % (95% CI) | 100 (71.5 to 100) | 95.6 (87.6 to 99.1) | 94.7 (85.4 to 98.9) |
| (n/N) | 11/11 | 65/68 | 54/57 |
| PPV % (95% CI) | 100 (94.2 to 100) | 97.1 (91.6 to 99.4) | 92.5 (79.6 to 98.4) |
| NPV % (95% CI) | 78.6 (49.2 to 95.3) | 80.2 (69.9 to 88.3) | 80.6 (69.1 to 89.2) |
PPV, positive predictive value; NPV, negative predictive value.
Predictive values were calculated for the given prevalence—that is, 61.5% for all patients (115/183), 85.5% for patients with sputum cultures (65/76), and 45.0% for patients with swabs (50/107).