[1] NHSBT, Clin Haematol, Birmingham, W Midlands, England
[2] Univ Hosp Birmingham, Birmingham, W Midlands, England
[3] Oxford Univ Hosp NHS Fdn Trust, Clin Haematol, Oxford, England
[4] NHS Blood & Transplant, Clin Trials Unit, Cambridge, England
[5] NHS Blood & Transplant, Clin Haematol, Oxford, England
[6] Oxford Univ Hosp NHS Fdn Trust, Oxford, England