Table 2.

Summary of included studies. References are reported in the Supplementary Material.

Outcome	Number of studies	Number of patients	Effect estimate (95%CI, p)
In-hospital mortality	18	123,923	OR= 0.94 (0.83-1.07, p=0.35)
ICU mortality	16	56,408	OR= 0.94 (0.79-1.13, p=0.51)
ICU LOS	22	48,222	SMD= 0.23 (0.11-0.35, p<0.01)
ECMO implantation	11	10,019	OR= 1.64 (1.06-2.52, p=0.03)
Mechanical ventilation time	14	8,870	SMD= 0.10 (-0.01-0.21, p=0.09)
Hospital LOS	14	16,343	SMD= 0.10 (-0.04-0.24, p=0.17)
Systemic thromboembolism	9	3,135	OR= 1.25 (0.82-1.91, p=0.29)
Myocarditis	6	6,330	OR= 1.49 (0.72-3.07, p=0.28)
Ventilator associated pneumonia	6	5,583	OR= 0.78 (0.51-1.18, p=0.24)

CI, confidence interval; ECMO, extracorporeal membrane oxygenation; LOS, length of stay; SMD, standard mean difference; OR, odds ratio.