[1] Cent Middlesex Hosp, London North West Healthcare NHS Trust, Haematol & Sickle Cell Ctr, London, England
[2] Imperial Coll London, Fac Med, London, England
[3] Komfo Anokye Teaching Hosp, Directorate Child Hlth, Kumasi, Ghana
[4] Kwame Nkrumah Univ Sci & Technol, Kumasi Ctr Collaborat Res Trop Med, Kumasi, Ghana
[5] Kwame Nkrumah Univ Sci & Technol, Sch Publ Hlth, Kumasi, Ghana
[6] Kwame Nkrumah Univ Sci & Technol, Dept Child Hlth, Kumasi, Ghana
[7] Sickle Cell Fdn Ghana, Kumasi, Ghana
[8] Univ Pittsburgh, Ctr Translat & Int Hematol, Heart Lung & Blood Vasc Med Inst, Pittsburgh, PA USA
[9] Univ Ghana, Sch Biomed & Allied Hlth Sci, Accra, Ghana