Table 1.

Outcomes Based on COVID-19 Severity and Clinical Setting

Clinical Context/ Severity of Illness	Key Patient-important Outcomes
Prophylactic trials	Rates of symptomatic disease with laboratory-confirmed SARS CoV-2 PCR positivity, rates of progression to severe disease and mortality.
Treatment trials in ambulatory patients with mild-moderate COVID-19 (SpO2 level>94% on room air)	Measures of important symptom improvement & deterioration, rates of hospitalization, rates of progression to severe disease, critical disease, and mortality. Later complications like MIS and rates and severity of post COVID conditions.
Treatment trials in hospitalized patients with mild-moderate COVID-19 (SpO2 level>94% on room air)	Measures of important symptom improvement & deterioration, rates of progression to severe disease, rates of progression to high flow oxygen, noninvasive or invasive mechanical ventilation and mortality. Later complications like MIS and rates and severity of post COVID conditions.
Treatment trials in hospitalized patients with severe COVID-19 (SpO2 level≤94% on room air) needing supplemental oxygen via a nasal cannula	Measures of important symptom improvement & deterioration, rates of progression to high flow oxygen, noninvasive or invasive mechanical ventilation and mortality. Later complications like MIS and rates and severity of post COVID conditions.
Treatment trials in hospitalized patients with COVID-19 requiring high-flow oxygen or non-invasive ventilation	Measures of important symptom improvement & deterioration, rates of progression to invasive mechanical ventilation and mortality. Later complications like MIS and rates and severity of post COVID conditions.
Treatment trials in hospitalized patients with COVID-19 requiring invasive mechanical ventilation, extracorporeal membrane oxygenation, or shock needing vasopressors	Mortality, ventilator-free days, ICU-free days and measures of symptom improvement and disability. Later complications like MIS and rates and severity of post COVID conditions.

Abbreviations: COVID-19, coronavirus disease 2019; ICU, intensive care unit; MIS, multisystem inflammatory syndrome; PCR, polymerase chain reaction; SARS-CoV-2, severe acute respiratory syndrome coronavirus 2.