[1] Univ Ibadan, Dept Hematol, Coll Med, Ibadan, Nigeria
[2] Univ Illinois, Div Hematol Oncol, Chicago, IL USA
[3] Univ Illinois, Hematol Oncol Sect, Dept Med, Ctr Comprehens Sickle Cell, Chicago, IL USA
[4] Univ Coll Hosp, Dept Hematol, Ibadan, Nigeria
[5] Univ Illinois, Pediat, Chicago, IL USA
[6] Loyola Univ Chicago, Dept Publ Hlth Sci, Maywood, IL USA
[7] Univ Illinois, Hematol Oncol Sect, Dept Med, Chicago, IL USA