1. Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
2. Department of Pediatrics, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania
3. Department of Pediatrics, University at Buffalo, The State University of New York, Buffalo, New York
4. Division of Pulmonology, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio
5. Department of Physical Medicine and Rehabilitation and
6. Division of Pulmonary and Critical Care Medicine, University of Washington School of Medicine, Seattle, Washington
7. MetroHealth Medical Center, Cleveland, Ohio
8. Case Western Reserve University, Cleveland, Ohio
9. Department of Neurology, Stanford University, Stanford, California
10. Parent Project Muscular Dystrophy, Hackensack, New Jersey; and
11. Department of Pediatrics, University of California Davis, Sacramento, California
12. Department of Neurology, Washington University School of Medicine, Saint Louis, Missouri