1. Children’s Heart Institute, MemorialCare Miller Children’s and Women’s Hospital Long Beach California
2. Memorial Heart and Vascular Institute, Long Beach Memorial Medical Center Long Beach California
3. Department of Epidemiology and Biostatistics University of Georgia College of Public Health Athens Georgia
4. Department of Pediatrics Emory University School of Medicine Atlanta Georgia
5. Departments of Pediatrics and Medicine University of Minnesota Minneapolis Minnesota
6. Children’s Healthcare of Atlanta Atlanta Georgia