1 Clinical Trials Unit, Intensive Care National Audit & Research Centre (ICNARC), London, UK.
2 Department of Health Services Research and Policy, London School of Hygiene & Tropical Medicine, London, UK.
3 John Radcliffe Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, UK.
4 Kadoorie Centre for Critical Care Research and Education, NIHR Biomedical Research Centre, Oxford, Oxford University Hospitals NHS Foundation Trust, Oxford, UK.
5 UK Renal Registry, Bristol, UK.
6 Population Health Sciences, University of Bristol, Bristol, UK.
7 Department of Clinical and Experimental Medicine, Faculty of Health Sciences, University of Surrey, Guildford, UK.
8 Intensive Care Unit, Royal Surrey County Hospital NHS Foundation Trust, Guildford, UK.
9 Patient representative, Oxford, UK.
10 Department of Intensive Care, Guy's and St Thomas' NHS Foundation Trust, London, UK.