“…All selected articles were rigorously appraised by two authors according to a modified version of the Dutch Cochrane center critical review checklist proposed by MOOSE (Stroup et al, 2000). Key domains assessed by the MOOSE tool include: (I) Clear definition of study population; (II) Clear definition of outcomes and outcomes assessment; (III) Independent assessment of outcome parameters; (IV) Sufficient The presence of SARS-CoV2 antibodies in MS patients (Armstrong et al, 2021;Arrambide et al, 2021;Barzegar et al, 2020Barzegar et al, , 2021Bose and Galetta, 2021;Bsteh et al, 2021;Chaudhry et al, 2020;Ciampi et al, 2020;Conte, 2020;Czarnowska et al, 2021;D'Abramo et al, 2021;Devogelaere et al, 2020;Fernandez-Diaz et al, 2021;Fragoso et al, 2021;Garg et al, 2020;Hervas-Garcia, 2020;Loonstra et al, 2020;Louapre et al, 2020;Montero-Escribano et al, 2020;Olivares Gazca et al, 2020;Sahraian et al, 2020;Salter et al, 2021;Sen et al, 2021;Sormani et al, 2021b,a;Spelman et al, 2021;Stroup et al, 2000;Suwanwongse and Shabarek, 2020;Thornton and Harel, 2020 *Data provided by the authors but not published.…”