“…Upon identification of 753 univocal records, we selected 40 pertinent manuscripts. During the screening phase of these manuscripts, 15 were excluded: three studies did not report mortality data or compared mortality rate with national registries (Bradfute et al, 2020;Dulipsingh et al, 2020;Perotti et al, 2020); for two studies, we were unable to assess our inclusion criteria (Anakli et al, 2021;Skrip et al, 2020); seven had no comparative group (Dulipsingh et al, 2020;Gonzá lez et al, 2020;Jaiswal et al, 2021;Madariaga et al, 2020;Olivares-Gazca et al, 2020;Tremblay et al, 2020;Valentini et al, 2020); and three studies made use of plasma from non-convalescent, generic donors (De-Simone et al, 2021;Faqihi et al, 2020;Kamran et al, 2021). Of the 25 studies included for the quantitative meta-analysis, 10 were RCTs (Agarwal et al, 2020;AlQahtani et al, 2020;Avendano-Sola et al, 2020;Balcells et al, 2021;Gharbharan et al, 2020;Horby et al, 2021;Li et al, 2020a;Libster et al, 2021;Rasheed et al, 2020;Simonovich et al, 2020), while the other 15 were non-randomized studies with different designs (Abolghasemi et al, 2020;Alsharidah et al, 2021;Altuntas et al, 2021;Budhiraja et al, 2021;Donato et al, 2021;Duan et al, 2020;Hegerova et al, 2020;Joyner et al, 2021;Liu et al, 2020;Omrani et al, 2021;Salazar et al, 2020a;…”