1. NHS Blood and Transplant; Systematic Review Initiative; Level 2, John Radcliffe Hospital Headington Oxford Oxon UK OX3 9BQ
2. John Radcliffe Hospital; Department of Geriatric Medicine; Headley Way Oxford UK OX3 9DU
3. Welsh Blood Service; Ely Valley Road Pontyclun Mid Glamorgan UK CF72 9WB
4. Oxford University Hospitals; Department of Trauma and Geratology; Level 4 Academic Corridor John Radcliffe Hospital Oxford UK OX3 9DU
5. Oxford University Hospitals and the University of Oxford; NHS Blood and Transplant; National Institute for Health Research (NIHR) Oxford Biomedical Research Centre; John Radcliffe Hospital Headington Oxford UK
6. Oxford University Hospitals and the University of Oxford; National Institute for Health Research (NIHR) Oxford Biomedical Research Centre; Oxford UK