1. 1National Disease Registration Service, NHS England, London, United Kingdom
2. 2NHS Blood and Transplant, Oxford, United Kingdom
3. 3Oxford University Hospitals NHS Trust, John Radcliffe Hospital, Oxford, United Kingdom
4. 4Radcliffe Department of Medicine, University of Oxford, NIHR Blood and Transplant Research Unit in Data Driven Transfusion Practice, Oxford, United Kingdom
5. 5Translational Medical Sciences, University of Nottingham, Nottingham, United Kingdom
6. 6Department of Haematology, Nottingham City Hospital, Nottingham, United Kingdom
7. 7Department of Haematology, Royal Devon and Exeter Hospital, Exeter, United Kingdom