An adapted version of the Brighton Collaboration priority list was used to evaluate serious adverse events (SAE) of special interest observed in mRNA Covid-19 vaccine trials. In December of 2020, reviewers searched journal publications and trial data on the FDA’s and Health Canada’s websites to locate SAE results tables for these trials. For each trial, blinded SAE tables were prepared. Using these blinded SAE tables, two clinician reviewers judged whether each SAE type was an adverse event of special interest (AESI). Risk ratios and risk differences between vaccine and placebo groups were calculated for the incidence of AESIs and SAEs.