Figure 2.

Design of the ACTION trial (study flowchart). Legend: A) 8-point ordinal COVID-19 outcome: death; invasive mechanical ventilation and support for another organ dysfunction; invasive mechanical ventilation alone; noninvasive ventilation/high-flow oxygen; hospitalized on supplemental oxygen; hospitalized not requiring supplemental oxygen; not hospitalized, limitation on activities and/or requiring home oxygen; not hospitalized, no limitations on activities. B) Disease progression: Mild defined as cases without criteria to be classified within the “moderate” or “severe” groups; Moderate: Oxygen saturation <94% or pulmonary infiltrates> 50% or ratio of partial pressure of arterial oxygen to fraction of inspired oxygen <300; Severe: Respiratory failure or hemodynamic instability or multiple organ dysfunction.