1. Department of Medicine, Addenbrooke's Hospital, Cambridge CB2 0QQ
2. Department of Medical Biochemistry and Immunology, University Hospital of Wales, Cardiff CF14 4XW
3. Department of Clinical Chemistry, Leeds General Infirmary, Leeds LS1 3EX
4. Department of Haematology, King's College Hospital, London SE5 9RS
5. University of Manchester, Manchester Academic Health Sciences Centre, Department of Clinical Biochemistry, Salford Royal NHS Foundation Trust, Salford M6 8HD, UK