evidence: In summary, although we find an increased risk of neurological complications in those who received COVID-19 vaccines, the risk of these complications is greater following a positive SARS-CoV-2 test. [...] Since the start of large-scale vaccine programs across the world, additional case reports have linked other neurological adverse events to COVID-19 vaccination, including Guillain–Barré syndrome9,10,11. Furthermore, surveillance studies have found a possible link between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and neurological events, including Guillain–Barré syndrome and myelitis12,13. However, case reports and surveillance studies are limited by small numbers, as well as potential selection and recording biases. Therefore, detailed assessments of potential neurological adverse events associated with COVID-19 vaccines and infection are urgently needed.