1. Warwick Clinical Trials Unit University of Warwick UK
2. Department of Anaesthesia and Intensive Care Medicine Royal United Hospitals Bath NHS Foundation Trust Bath UK
3. Department of Anaesthesia and Intensive Care Medicine, Southmead Hospital Bristol UK
4. Health Services Research Centre Royal College of Anaesthetists Red Lion Square UK
5. Department of Anaesthesia James Cook University Hospital, South Tees NHS Foundation Trust Middlesbrough UK
6. University of Nottingham Nottingham UK
7. Severn Deanery Bristol UK
8. University of Bristol Bristol UK