1. Health Economics Research Centre, Nuffield Department of Population Health; University of Oxford; Oxford United Kingdom
2. Radcliffe Department of Medicine; University of Oxford; Oxford United Kingdom
3. NHS Blood and Transplant/Oxford University Hospitals NHS Trust; John Radcliffe Hospital; Oxford United Kingdom
4. NHSBT/MRC Clinical Studies Unit; NHS Blood and Transplant; Cambridge United Kingdom
5. Transfusion Research Unit, Department of Epidemiology and Preventive Medicine; Monash University; Melbourne Australia