1. Semel Institute of Neuroscience and Human Behavior, David Geffen School of MedicineUniversity of California, Los Angeles Los Angeles California USA
2. Department of Medicine Statistics CoreDavid Geffen School of Medicine Los Angeles California USA
3. Gait and Balance Academy, Protokinetics Havertown Pennsylvania USA
4. Laboratory Performance, Sante, Metrologie, Societe (PSMS), UFR STAPS Reims France
5. Division of Biokinesiology and Physical Therapy and Department of PediatricsUniversity of Southern California Los Angeles California USA
6. Greater Los Angeles VA HealthCare System, Department of NeurologyUniversity of California, Los Angeles Los Angeles California USA