Table 5 Difference in length of intensive care unit stay between the three study periods in severity subgroups of the study population

High severity of illness

ICU length of stay, days, median (IQR)

2.4 (1.13–5.02)

2.06 (1.05–4.64)*

2.4 (1.21–4.71)

28–day ICU free days, median (IQR)

23.2 (0.0–26.2)

24.1 (0.0–26.4) *

24.4 (0.0–26.3)*

Low severity of illness

ICU length of stay, days, median (IQR)

1.0 (0.75–1.99)

1.0 (0.72–1.93)

1.1 (0.77–1.99)

28-day ICU free days, median (IQR)

26.9 (25.9–27.3)

26.9 (26.0–27.3)

26.9 (25.9–27.2)