1. From the Department of Haematology, University College London Hospitals NHS Foundation Trust (M.S., M.L.), National Institute for Health Research University College London Hospitals Biomedical Research Centre (M.S., M.L.), Special Coagulation, Health Services Laboratories (D.S.), Great Ormond Street Institute of Child Health, University College London (D.G.), and National Institute for Health Research Great Ormond Street Biomedical Research Centre (D.G.), London, the Department of Haematology, University...