1. Department of Pediatrics, Miller School of Medicine at the University of Miami, Holtz Children's Hospital of the University of Miami-Jackson Memorial Medical Center, and the Sylvester Comprehensive Cancer Center, Miami, Florida
2. Department of Cardiology and
3. Department of Biometry and Epidemiology, Medical University of South Carolina, Charleston, South Carolina
4. Division of Hematology-Oncology, Children's Hospital, Boston, Massachusetts
5. Department of Pediatrics, Harvard Medical School, Boston, Massachusetts
6. Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts