1 Paediatric Haematology, Evelina London Children's Hospital, Guy's and St Thomas NHS Foundation Trust, London SE1 7EH, UK; Women's and Children's Health, Faculty of Life Sciences and Medicine, King's College London, London, UK. Electronic address: baba.inusa@gstt.nhs.uk.
2 Department of Paediatric Haematology, UCLA School of Nursing, Los Angeles, CA, USA.
3 Department of Haematology, Faculty of Basic Clinical Sciences, Kaduna State University College of Medicine, Kaduna, Nigeria.
4 Haematology and Sickle Cell Centre, Central Middlesex Hospital, London North West University Healthcare NHS Trust, London, UK; Faculty of Medicine, Imperial College London, London, UK.