Diagnostic performance of the predictors of CAP in the elderly
| CAP+ (n=27) | CAP− (n=82) | Sensitivity (95% CI) | Specificity (95% CI) | LR+ (95% CI) | LR− (95% CI) | DOR (95% CI) | Cut-off point | |
| Cough (%) | 100 | 98.8 | 100 (87.2 to 100) | 1.2 (0.3 to 6.6) | 1.0 (1.0 to 1.0) | 0 | – | – |
| Sputum (%) | 88.9 | 74.1 | 88.9 (70.8 to 97.6) | 25.9 (16.8 to 36.9) | 1.2 (1.0 to 1.4) | 0.4 (0.1 to 1.3) | 2.8 (0.8 to 9.6) | – |
| Sore throat (%) | 22.2 | 40.2 | 22.2 (8.6 to 42.3) | 59.8 (48.3 to 70.4) | 0.6 (0.3 to 1.2) | 1.3 (1.0 to 1.7) | 0.4 (0.2 to 1.1) | – |
| Rhinorrhea (%) | 34.6 | 60.5 | 34.6 (17.2 to 55.7) | 39.5 (28.8 to 51.0) | 0.6 (0.3 to 1.0) | 1.7 (1.1 to 2.4) | 0.3 (0.1 to 0.9) | – |
| Dyspnoea (%) | 40.7 | 34.2 | 40.1 (22.4 to 61.2) | 65.9 (54.6 to 76.0) | 1.2 (0.7 to 2.1) | 0.9 (0.6 to 1.3) | 1.3 (0.6 to 3.2) | – |
| Fever (%) | 74.1 | 35.4 | 74.1 (53.7 to 88.9) | 64.6 (53.3 to 74.9) | 2.1 (1.5 to 3.0) | 0.4 (0.2 to 0.8) | 5.2 (2.0 to 13.5) | – |
| Chill (%) | 29.6 | 27.2 | 29.6 (13.8 to 50.2) | 71.6 (60.5 to 81.1) | 1.0 (0.5 to 2.1) | 0.98 (0.7 to 1.3) | 1.1 (0.4 to 2.7) | – |
| Night sweats (%) | 33.3 | 24.4 | 33.3 (16.5 to 54.0) | 75.6 (64.9 to 84.4) | 1.4 (0.7 to 2.6) | 0.9 (0.7 to 1.2) | 1.5 (0.6 to 3.9) | – |
| Myalgia (%) | 7.4 | 18.3 | 7.4 (0.9 to 24.3) | 81.7 (71.6 to 89.4) | 0.4 (0.1 to 1.7) | 1.1 (1.0 to 1.3) | 0.4 (0 to 1.5) | – |
| Pleural pain (%) | 7.4 | 7.4 | 7.4 (0.9 to 24.3) | 92.6 (84.6 to 97.2) | 1.0 (0.2 to 4.7) | 1.0 (0.9 to 1.1) | 1.0 (0 to 4.7) | – |
| Diarrhoea (%) | 7.4 | 7.4 | 7.4 (0.9 to 24.3) | 92.6 (84.6 to 97.2) | 1.0 (0.2 to 4.7) | 1.0 (0.9 to 1.1) | 1.0 (0 to 4.7) | – |
| Duration of symptoms (days) | 6.1 | 7.2 | 42.3 (23.4 to 63.1) | 62.5 (51.0 to 73.1) | 1.1 (0.7 to 1.9) | 0.9 (0.6 to 1.3) | 1.2 (0.5 to 3.0) | 7 days from the model by Melbye et al9 |
| Coma (%) | 15.4 | 6.1 | 15.4 (4.4 to 34.9) | 93.9 (86.3 to 98.0) | 2.5 (0.7 to 8.7) | 0.9 (0.8 to 1.1) | 2.8 (0.7 to 10.6) | – |
| Fall (%) | 11.1 | 1.2 | 11.1 (2.4 to 29.2) | 98.8 (93.4 to 100.0) | 9.1 (1.0 to 84.0) | 0.9 (0.8 to 1.0) | 10.1 (1.4 to ∞) | – |
| Appetite loss (%) | 48.8 | 80.1 | 66.7 (46.0 to 83.5) | 79.3 (68.9 to 87.4) | 3.2 (2.0 to 5.3) | 0.4 (0.2 to 0.7) | 7.7 (3.0 to 19.7) | 50% determined by the ROC curve |
| SBP (mm Hg) | 129.9 | 130.1 | 3.7 (0.1 to 19.0) | 100 (95.6 to 100) | – | 1.0 (0.9 to 1.0) | – | 90 mm Hg from CURB6516 |
| DBP (mm Hg) | 72.5 | 73.9 | 22.2 (8.6 to 42.3) | 84.1 (74.4 to 91.3) | 1.4 (0.6 to 3.3) | 0.9 (0.7 to 1.2) | 1.4 (0.5 to 4.4) | 60 mm Hg from CURB6516 |
| Pulse rate (/min) | 89.3 | 82.8 | 29.6 (13.8 to 50.2) | 80.5 (70.3 to 88.4) | 1.5 (0.7 to 3.2) | 0.9 (0.7 to 1.1) | 1.7 (0.7 to 4.6) | 100/min from the model by van Vugt et al11 |
| SpO2 (%) | 93.7 | 96.4 | 51.9 (31.9 to 71.3) | 91.5 (83.2 to 96.5) | 6.1 (2.7 to 13.5) | 0.5 (0.4 to 0.8) | 11.5 (4.0 to 33.4) | 95% as normal value |
| Respiratory rate (/min) | 21.3 | 19.0 | 3.7 (0.1 to 19.0) | 100 (95.5 to 100) | – | 1.0 (0.9 to 1.0) | – | 30/min from CURB6516 |
| Body temperature (℃) | 37.6 | 36.7 | 29.6 (13.8 to 50.2) | 91.5 (83.2 to 96.5) | 3.5 (1.4 to 8.7) | 0.8 (0.6 to 1.0) | 4.5 (1.5 to 13.6) | 38°C from the model by Hopstaken et al10 |
| Decreased respiratory sound (%) | 18.5 | 4.9 | 18.5 (6.3 to 38.1) | 95.1 (87.8 to 98.6) | 3.8 (1.1 to 13.0) | 0.9 (0.7 to 1.0) | 4.4 (1.2 to 16.4) | – |
| Crackle (%) | 48.2 | 14.8 | 48.1 (28.7 to 68.1) | 85.2 (75.6 to 92.1) | 3.3 (1.7 to 6.2) | 0.6 (0.4 to 0.9) | 5.3 (2.1 to 14.0) | – |
| Wheeze (%) | 3.7 | 3.7 | 3.7 (0.1 to 19.0) | 96.3 (89.6 to 99.2) | 1.0 (0.1 to 9.2) | 1.0 (0.9 to 1.1) | 1.0 (0 to 7.4) | – |
| Rhonchi (%) | 3.7 | 6.2 | 3.7 (0.1 to 19.0) | 93.8 (86.2 to 98.0) | 0.6 (0.1 to 4.9) | 1.0 (0.9 to 1.1) | 0.6 (0 to 4.0) | – |
CAP, community-acquired pneumonia; CURB65, confusion, urea >7 mmol/L, respiratory rate ≥30 breaths/min, low blood pressure (systolic <90 mm Hg or diastolic ≤60 mm Hg); DBP, diastolic blood pressure; DOR, diagnostic OR; LR+, positive likelihood ratio; LR−, negative likelihood ratio; ROC, receiver operating characteristic; SBP, systolic blood pressure; SpO2, oxygen saturation.