Table 1 Initial variables of the whole cohort (fever > 72 h)
Training cohort (n = 501) | Test cohort (n = 215) | |||||
|---|---|---|---|---|---|---|
Fever ≥ 72 h | Fever < 72 h | p-value | Fever ≥ 72 h | Fever < 72 h | p-value | |
Number of patients (n, %) | 163 (32.5) | 338 (67.5) | 79 (36.7) | 136 (63.3) | ||
Age, mean (years) | 5.9 ± 2.8 | 5.5 ± 3.2 | 0.140 | 5.8 ± 2.5 | 5.3 ± 3.1 | 0.273 |
Sex ratio (female: male) | 1.3 | 1.0 | 0.124 | 1.7 | 0.7 | 0.002 |
Duration of fever (days) | ||||||
At admission | 4.8 ± 1.8 | 5.1 ± 2.2 | 0.057 | 4.9 ± 1.7 | 4.9 ± 2.0 | 0.960 |
After admission | 4.8 ± 3.4 | 1.3 ± 1.0 | < 0.001 | 4.9 ± 3.3 | 1.3 ± 0.9 | < 0.001 |
Total | 9.4 ± 3.3 | 6.5 ± 2.3 | < 0.001 | 9.5 ± 3.0 | 6.3 ± 2.1 | < 0.001 |
Total hospital days (days) | 9.2 ± 3.5 | 5.4 ± 1.6 | < 0.001 | 9.4 ± 3.6 | 5.5 ± 1.8 | < 0.001 |
Initial inflammatory markers | ||||||
WBC × 103/µL | 7.6 ± 3.5 | 9.6 ± 7.0 | 0.001 | 7.5 ± 3.2 | 9.7 ± 5.5 | < 0.001 |
Neutrophils (%) | 67.0 ± 10.7 | 63.0 ± 14.2 | 0.001 | 68.0 ± 10.8 | 61.9 ± 14.2 | 0.001 |
Absolute neutrophil count × 103/µL | 5.2 ± 2.9 | 6.2 ± 5.3 | 0.003 | 5.1 ± 2.4 | 6.2 ± 4.8 | 0.031 |
Lymphocytes (%) | 23.2 ± 8.4 | 26.6 ± 12.4 | < 0.001 | 22.9 ± 8.4 | 27.7 ± 12.8 | 0.001 |
Absolute lymphocyte count × 103/µL | 1.1 ± 0.5 | 1.4 ± 1.1 | < 0.001 | 1.1 ± 0.6 | 1.4 ± 0.7 | 0.001 |
Platelet × 103/µL | 242.0 ± 75.9 | 304.9 ± 100.4 | < 0.001 | 234.9 ± 71.1 | 308.6 ± 101.1 | < 0.001 |
ESR (mm/hr) | 38.3 ± 18.4 | 35.9 ± 18.5 | 0.178 | 37.4 ± 17.3 | 32.5 ± 17.4 | < 0.001 |
CRP (mg/L) | 49.2 ± 45.6 | 24.7 ± 30.6 | < 0.001 | 57.7 ± 53.9 | 24.1 ± 27.7 | < 0.001 |
Procalcitonin (ng/mL) | 0.6 ± 1.2 | 0.7 ± 2.4 | 0.700 | 0.5 ± 0.7 | 0.3 ± 0.6 | 0.169 |
Other laboratory data | ||||||
LDH (IU/L) | 359.8 ± 107.4 | 326.2 ± 73.1 | < 0.001 | 372.6 ± 132.8 | 332.7 ± 90.7 | 0.019 |
AST (IU/L) | 40.3 ± 17.9 | 36.2 ± 29.3 | 0.104 | 39.4 ± 14.9 | 41.5 ± 48.5 | 0.701 |
ALT (IU/L) | 19.6 ± 13.3 | 22.6 ± 64.9 | 0.556 | 15.9 ± 7.3 | 29.2 ± 77.9 | 0.051 |
Concurrent respiratory virus (n, %) | 36/140 (25.7) | 95/285 (33.3) | 0.110 | 18/64 (28.1) | 39/117 (33.3) | 0.471 |
Oxygen requirement (n, %) | 5 (3.1) | 8 (2.4) | 0.765 | 3 (3.8) | 2 (1.5) | 0.359 |
Radiologic grouping (n, %) | ||||||
Group 1 | 13 (8.0) | 108 (32.0) | < 0.001 | 7 (8.9) | 44 (32.4) | < 0.001 |
Group 2 | 54 (33.1) | 161 (47.6) | 22 (27.8) | 67 (49.3) | ||
Group 3 | 85 (52.1) | 68 (20.1) | 41 (51.9) | 24 (17.6) | ||
Group 4 | 11 (6.7) | 1 (0.3) | 9 (11.4) | 1 (0.7) | ||
Pleural effusion (n, %) | 34 (20.9) | 20 (5.9) | < 0.001 | 18 (22.8) | 6 (4.4) | < 0.001 |
Radiologic aggravation on the 3rd or 4th hospital day (n, %) | 121 (74.2) | 29 (8.6) | < 0.001 | 61 (77.2) | 15 (11.0) | < 0.001 |