. 2021 Jun 23;40(24):5131–5151. doi: 10.1002/sim.9115

TABLE 1.

WHO 11‐point COVID scale definition

0:	Uninfected, no viral RNA detected
1:	Asymptomatic, viral RNA detected
2:	Symptomatic, independent
3:	Symptomatic, assistance needed
4:	Hospitalized, no oxygen therapy
5:	Hospitalized, oxygen by mask or nasal prongs
6:	Hospitalized, oxygen by noninvasive ventilation or high flow
7:	Intubation & mechanical ventilation, pO $_{2}$ /FiO $_{2}$ $\geq$ 150 (or SpO $_{2}$ /FiO $_{2}$ $\geq$ 200)
8:	Mechanical ventilation, pO $_{2}$ /FiO $_{2}$ $<$ 150 (or SpO $_{2}$ /FiO $_{2}$ $<$ 200) or vasopressors
9:	Mechanical ventilation, pO $_{2}$ /FiO $_{2}$ $<$ 150 and vasopressors, dialysis, or ECMO
10:	Dead

Abbreviations: pO $_{2}$ , partial pressure of oxygen; ECMO, extracorporeal membrane oxygenation; FiO $_{2}$ , fraction of inspired oxygen; SpO $_{2}$ , oxygen saturation.