Funding
The trial was funded by the National Institute for Health and Care Research (NIHR), Research for Patient Benefit programme (PB-PG-1215-20041), and supported by the NIHR Oxford Biomedical Research Centre (BRC). The views expressed are those of the authors and not necessarily those of the NIHR or the Department of Health and Social Care. The study funders had no role in the study design, data collection, data analysis, interpretation, writing of the manuscript, or decision to submit for publication. All authors had access to all study data and take responsibility for its integrity and the accuracy of the data analysis. H.D. is partly funded by an NIHR Senior Research Fellowship through the Oxford BRC. D.J.B. is partly funded by the Royal College of Surgeons of England and the Rosetrees Trust. The trial sponsor was the University of Oxford.