1. University of Toronto, St. Michael's Hospital, Toronto, Ontario, Canada;
2. Harvard Vanguard Medical Associates, Beverly, MA;
3. Washington University, St. Louis, MO;
4. AE Health Consulting, Dunnville, Ontario, Canada;
5. Medical Specialists of Taunton, Taunton, MA;
6. University of Toronto, University Health Network, Toronto, Ontario, Canada;
7. University of North Carolina, Chapel Hill, NC;
8. All Children's Hospital Johns Hopkins Medicine, St. Petersburg, FL;
9. Nationwide Children's Hospital, Columbus, OH;
10. Medical College of Wisconsin/Children's Hospital of Wisconsin, Milwaukee, WI;
11. Medical College of Wisconsin, Milwaukee, WI;
12. University of Florida, Gainesville, FL; and
13. University of Texas Southwestern Medical Center, Dallas, TX