Table 1 Cohort characteristics

Age, median (range), years

0.6 (2days-15 years)

6 (1 month-20 years)

Gender, n (%)

 Male

642 (62.1)

4735 (56.2)

 Female

392 (37.9)

3691 (43.8)

Days in hospital, median (range), days

16 (3–329)

N/A

Diagnosed as primary severe pneumonia

719 (69.5)

N/A

Diagnosed as secondary severe pneumonia

315 (30.5)

N/A

Pathogens, n (%)

 Viral

721 (69.7)

N/A

 Bacterial

625 (60.4)

N/A

 Fugus

108 (10.4)

N/A

Comorbid conditions, n (%)

978 (94.6)

N/A

Complications

 Acute respiratory failure

344 (33.3)

N/A

 Acute respiratory distress syndrome (ARDS)

17 (1.6)

N/A

 Sepsis

70 (6.8)

N/A

Mechanical ventilation, n (%)

776 (75.0)

N/A

Clinical outcomes, n (%)

 Discharge

979 (94.7)

N/A

 Mortality

55 (5.3)

N/A