Table 3.
Statistical performance of different group of patients, samples and diseases.
| True positive (#) | False positive (#) | False negative (#) | True negative (#) | Sensitivity (%, 95%CI) | Specificity (%, 95%CI) | Positive predictive value (%, 95%CI) | Negative predictive value (%, 95%CI) | |
|---|---|---|---|---|---|---|---|---|
| overall | 169 | 14 | 6 | 103 | 96.6 (92.3-98.6) | 88.0 (80.4-93.1) | 92.3 (87.2-95.6) | 94.5 (87.9-97.7) |
| ICU | 95 | 7 | 4 | 44 | 96.0 (89.4-98.7) | 86.3 (73.1-93.8) | 93.1 (85.9-97.0) | 91.7 (79.1-97.3) |
| General wards | 74 | 7 | 2 | 59 | 97.4 (90.0-99.5) | 89.4 (78.8-95.3) | 91.4 (82.5-96.2) | 96.7 (87.6-99.4) |
| BALF | 95 | 10 | 4 | 62 | 96.0 (89.4-98.7) | 86.1 (75.5-92.8) | 90.5 (82.8-95.1) | 93.9 (84.4-98.0) |
| Sputum | 74 | 4 | 2 | 41 | 97.4 (90.0-99.5) | 91.1 (77.9-97.1) | 94.9 (86.7-98.3) | 95.3 (82.9-99.2) |
| AECOPD | 19 | 1 | 1 | 12 | 95.0 (73.1-99.7) | 92.3 (62.1-99.6) | 95.0 (73.1-99.7) | 92.3 (62.1-99.6) |
| CAP | 41 | 4 | 1 | 37 | 97.6 (85.9-99.9) | 90.2 (75.9-96.8) | 91.1 (77.9-97.1) | 97.4 (84.6-99.9) |
| CAP-ICH | 25 | 2 | 1 | 16 | 96.2 (78.4-99.8) | 88.9 (63.9-98.1) | 92.6 (74.2-98.7) | 94.1 (69.2-99.7) |
| HAP | 51 | 2 | 2 | 11 | 96.2 (85.9-99.3) | 84.6 (53.7-97.3) | 96.2 (85.9-99.3) | 84.6 (53.7-97.3) |
| AEBX | 24 | 3 | 1 | 16 | 96.0 (77.7-99.8) | 84.2 (59.5-95.8) | 88.9 (69.7-97.1) | 94.1 (69.2-99.7) |
| Lung abscess | 9 | 2 | 0 | 11 | 100.0 (62.9-100.0) | 84.6 (53.7-97.3) | 81.8 (47.8-96.8) | 100.0 (67.9-100.0) |
Patient groups include: patients from ICU (intensive care unit) and from general wards.
Sample groups include: sputum and BALF (bronchoalveolar lavage fluid).
Disease groups include: AECOPD, Acute exacerbation of chronic obstructive pulmonary; CAP, community acquired pneumonia; CAP-ICH, community-acquired pneumonia in immunocompromised host; HAP, Hospital Acquired Pneumonia; AEBX, acute exacerbation of bronchiectasis and lung abscess.
95%CI: 95% confidence intervals, it was calculated in http://vassarstats.net/clin1.html#return.