Editor’s note: The authors and editors reviewed a complaint that the methods used in this paper published in The BMJ in 2019 are outdated and flawed and, as a consequence, that the findings are unreliable. The authors agree that the methods used are now outdated, however, the methods were considered reasonable at the time of publication. BMJ, following further review, does not judge that a post-publication correction is required due to outdated methods. A new analysis answering the same research question but using more current analytical methods is now published in BMJ Open [1]. The new analysis finds that the relationship between low BMI and mortality is uncertain. The author groups of the two articles overlap, but are not the same. The co-authors Stephen Burgess, Yi-Qian Sun, Amy M Mason and Xiao-Mei Mai are authors of the updated paper published in BMJ Open.
[1] Burgess S, Sun Y, Zhou A, et al. Body mass index and all-cause mortality in HUNT and UK biobank studies: revised non-linear Mendelian randomisation analyses. BMJ Open 2024;14:e081399. doi: 10.1136/bmjopen-2023-081399
Footnote: An earlier version of this Editor’s Note was posted on 30 May 2024.
Re: Body mass index and all cause mortality in HUNT and UK Biobank studies: linear and non-linear mendelian randomisation analyses