1. Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, MD;
2. Canadian Sport Institute Ontario, Toronto, Canada;
3. Division of Cardiology, Department of Internal Medicine, Ohio State University, Columbus, OH;
4. University of Iowa Stead Family Children's Hospital, Iowa City, IA;
5. Indiana University School of Medicine, Bloomington, IN;
6. Massachusetts General Hospital, Harvard Medical School, Boston, MA;
7. Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD;
8. Indiana University Schol of Medicine, Indianapolis, IN;
9. Department of Family Medicine and Community Health, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ;
10. Department of Rehabilitation and Human Performance, Icahn School of Medicine at Mount Sinai, New York, NY;
11. Department of Orthopaedics and Rehabilitation, Pennsylvania State University, State College, PA; and
12. University of Virginia, Charlottesville, VA.