1. Versiti Wisconsin & The Medical College of Wisconsin Milwaukee Wisconsin USA
2. Yale University School of Medicine New Haven Connecticut USA
3. Children's Hospital of PhiladelphiaPerelman School of Medicine at the University of Pennsylvania Philadelphia Pennsylvania USA
4. Bayero University/Aminu Kano Teaching Hospital Kano Nigeria
5. University of Washington Medical Center Seattle Washington USA
6. Phoenix Children's Hospital Phoenix Arizona USA
7. New York Blood Center New York New York USA
8. Columbia University Irving Medical Center New York New York USA
9. Children's National Hospital Washington District of Columbia USA
10. Vanderbilt University Medical Center (VUMC) Nashville Tennessee USA