Comparison 3. Adequate allocation concealment (sensitivity analysis).

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Mortality at the end of the follow‐up period	4	2320	Risk Ratio (M‐H, Random, 95% CI)	0.88 [0.60, 1.28]
2 Death or severe disability (GOS 1 to 3) at the end of the follow‐up period	4	2260	Risk Ratio (M‐H, Fixed, 95% CI)	0.98 [0.89, 1.06]