1 Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada.
2 Children's Hospital of Michigan, Detroit, Michigan; Central Michigan University School of Medicine, Saginaw, Michigan.
3 City of Hope Comprehensive Cancer Center, Duarte, California.
4 Boston Children's Hospital and Dana-Farber Cancer Institute, Boston, Massachusetts.
5 University of Michigan, C.S. Mott Children's Hospital, Ann Arbor, Michigan.
6 Cedars-Sinai Heart Institute, Los Angeles, California.
7 Lurie Children's Hospital, Chicago, Illinois.
8 St. Jude Children's Research Hospital/University of Tennessee College of Medicine, Memphis, Tennessee.
9 University of Washington, Seattle Children's Hospital, Seattle, Washington.
10 University at Buffalo Jacobs School of Medicine and Biomedical Sciences, Oishei Children's Hospital, Roswell Park Comprehensive Cancer Center, Buffalo, New York.
11 Lee Health Heart Institute, Fort Myers, Florida.
12 University of California San Diego, Rady Children's Hospital San Diego, San Diego, California.
13 Texas Children's Hospital, Baylor College of Medicine, Houston, Texas.
14 Connecticut Children's Medical Center, University of Connecticut School of Medicine, Hartford, Connecticut.
15 Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.