[1] John Walton Muscular Dystrophy Res Ctr, Newcastle Upon Tyne, Tyne & Wear, England
[2] Childrens Natl Hlth Syst, Ctr Translat Sci, Div Biostat & Study Methodol, Washington, DC USA
[3] George Washington Univ, Pediat Epidemiol & Biostat, Washington, DC USA
[4] Elan Physio, Berlin, Germany
[5] Stanford Univ, Sch Med, Dept Neurol & Neurol Sci, Stanford, CA 94305 USA
[6] Childrens Hosp Westmead, Inst Neurosci & Muscle Res, Sydney, NSW, Australia
[7] Childrens Natl Hlth Syst, Dept Neurol, Washington, DC USA
[8] Aix Marseille Univ, La Timone Hosp, Neuromuscular & ALS Ctr, Marseille, France
[9] Washington Univ, Sch Med, Dept Neurol, St Louis, MO USA
[10] Ludwig Maximilians Univ Munchen, Friedrich Baur Inst, Dept Neurol, Munich, Germany
[11] Hosp Univ Virgen Rocio, Inst Biomed Sevilla, Dept Neurol, Neuromuscular Unit, Seville, Spain
[12] AP HP, Inst Myol, GH Pitie Salpe Triere 47-83,Blvd Hop, Paris, France
[13] Natl Ctr Neurol & Psychiat Tokyo, Natl Ctr Hosp, Dept Neurol, Tokyo, Japan
[14] Carolinas Healthcare Syst Neurosci Inst, Charlotte, NC USA
[15] Hosp Santa Creu & Sant Pau, Neurol Dept, Neuromuscular Disorders Unit, Barcelona, Spain
[16] Univ Padua, Dept Neurosci, Padua, Italy
[17] Nationwide Childrens Hosp, Columbus, OH USA