Fig. 3

Forest plot of HRs for the primary endpoint in different subgroups of the matched cohort. HR: Hazard Ratio, CI: Confidence Interval, SOFA Sequential Organ Failure Assessment, PO2 partial pressure of oxygen, FiO2 Fraction of Inspired Oxygen, SOFA quartile Q1:<4; Q2:4–5; Q3:6–8; Q4:≥9, NIV non-invasive ventilation, invasive mechanical ventilation IMV