1 Epidemiology of Cancer Healthcare Outcomes (ECHO) Group, Department of Behavioural Science and Health, University College London, London.
2 ECHO Group, Department of Behavioural Science and Health, University College London, London.
3 North Middlesex University Hospital, London, UK.
4 The Royal Marsden and The Institute for Cancer Research National Institute for Health Research (NIHR) Biomedical Research Centre (BRC), The Royal Marsden NHS Foundation Trust, London.