1. Marie Curie Palliative Care Research Department, Division of Psychiatry, University College London (UCL), London, United Kingdom
2. University Hospitals Sussex NHS Foundation Trust, Worthing Hospital, Lyndhurst Road, Worthing, West Sussex, United Kingdom
3. University of Southampton & University Hospital Southampton NHS Foundation Trust, Southampton General Hospital, Southampton, United Kingdom
4. Department of Primary Care & Population Health, Institute of Epidemiology & Health Care, Faculty of Population Health Sciences, University College London (UCL), London, United Kingdom
5. Comprehensive Clinical Trials Unit, University College London (UCL), London, United Kingdom