Competing interestsThe BMJ has judged that there are no disqualifying financial ties to commercial companies. The authors declare the following other interests: TQ and KG are supported by Stroke Association/ Chief Scientist Office Clinical Lectureships. SPM receives support from Institute for Evidence Based Medicine in Older Age. JKB is supported by the Scottish Clinical Research Excellence Development Scheme funded by NHS Education for Scotland. Further details of The BMJ policy on financial interests is here: https://www.bmj.com/about-bmj/resources-authors/forms-policies-and-checklists/declaration-competing-interests All authors contributed to researching the manuscript, drafting and editing and obtaining expert review from patients, carers and other stakeholders.