Patient characteristics
| All patients | PCR positive | PCR negative | p-value | |
| Subjects n | 187# | 86 | 100 | |
| Age years | 63.7±15.7 | 63.4±14.8 | 64.1±16.5 | 0.668 |
| Male | 108 (57.8) | 50 (58.1) | 58 (58.0) | 0.97 |
| Admission | 140 (74.9) | 65 (75.6) | 75 (75.0) | 0.855 |
| Admission ED to IC | 9 (4.8) | 8 (9.3) | 1 (1.0) | <0.001 |
| In hospital mortality | 9 (4.8) | 5 (5.8) | 4 (4.0) | 0.001 |
| Obesity (based on clinical assessment) | 52 (27.8) | 27 (31.4) | 25 (25) | 0.676 |
| Duration of symptoms days | 6.5±5.1 | 7.3±4.1 | 5.8±5.8 | 0.007 |
| Comorbidities | ||||
| Asthma | 10 (5.3) | 3 (3.5) | 7 (7.0) | 0.033 |
| Chronic cardiovascular disease | 44 (23.5) | 18 (20.9) | 26 (26.0) | 0.104 |
| COPD (GOLD stage >2) | 30 (5.3) | 12 (14.0) | 18 (18.0) | 0.134 |
| Current malignancy | 35 (18.7) | 9 (10.5) | 26 (26.0) | <0.001 |
| Diabetes mellitus | 36 (19.3) | 21 (24.4) | 15 (15.0) | 0.001 |
| Laboratory analysis on admission | ||||
| CRP mg·L−1 median (interquartile range) | 59 (81.5) | 68 (83.8) | 49.0 (80.8) | 0.73 |
| Procalcitonin ng·mL−1 median (interquartile range) | 0.1 (0.25) | 0.12 (0.21) | 0.1 (0.37) | 0.004 |
| Positive blood culture | 12 (6.4) | 1 (1.2) | 11 (11.0) | 0.204 |
| Positive influenza A/B | 0 | 0 | 0 | 0.593 |
| Observations | ||||
| Modified early warning score (MEWS) | 2.6±1.8 | 2.9±1.6 | 2.3±1.8 | 0.605 |
| Temperature °C | 37.5±1.2 | 37.8±1.1 | 37.2±1.3 | 0.174 |
| Respiratory rate min-1 | 21.2±6.9 | 21.9±7.2 | 20.7±6.7 | 0.888 |
| Oxygen saturation % | 95.8±3.2 | 94.9(3.5 | 96.4±2.8 | 0.165 |
| Oxygen therapy | 58 (0.31) | 34 (39.5) | 24 (24.0) | 0.004 |
| Intubation | 9 (4.8) | 8 (9.3) | 1 (1.0) | <0.001 |
Data are presented as mean±sd or n (%), unless otherwise stated. Statistically significant differences between the PCR positive and PCR negative groups are emphasised in bold text. ED: emergency department; IC: intensive care; GOLD: Global Initiative for Chronic Obstructive Lung Disease; CRP: C-reactive protein. #: One patient had an indeterminate PCR and no repeat PCR, therefore the total amount of patients (187) differs from the sum of the PCR positives (86) and PCR negatives (100).