Table 2. Risk of bias of the randomized controlled trials included in the analysis.

Cochrane risk-of-bias (RoB 2) tool
Study	Randomization	Allocation	Double blinding	Observer	Losses	CP	Outcome	ITT	Sample size calculation	Early stop trial
Beigel et al. 16
Spinner et al. 19
Wang et al. 20
WHO Solidarity Trial Consortium et al. 18
Mahajan et al. 17
Ader et al. 21

CP: characteristic prognosis; and ITT: intention to treat.

Observation: red = risk of bias; yellow = not clear; green = no risk of bias.