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First published online: 20 September 2020, Int J Epidemiol 2020; doi: https://doi.org/10.1093/ije/dyaa121
Upon the original publication of this article, the publication history was incorrect. This has been corrected to read: “Received 29 March 2020; Editorial decision 18 June 2020; Accepted 19 June 2020”. The publisher apologises for the error.
