Acknowledgements
We are very grateful to the staff and participants at the trial centres. The trial was conducted in collaboration with Norwich CTU whose staff supported the design, conduct and analysis of the trial, including the data management team Antony Colles & Maria Leathersich. We thank Ms. Sarah Doyle, Research Administrator for her support with study management. This study is sponsored by the Norfolk & Norwich University Hospitals NHS Trust (rdoffice@nnuh.nhs.uk).