[1] US Vet Hlth Adm, MS Ctr Excellence West, Seattle, WA 98101 USA
[2] Univ Washington, Dept Rehabil & Epidemiol, Seattle, WA 98195 USA
[3] Univ Washington, MS Rehabil Res & Training Ctr, Seattle, WA 98195 USA
[4] Evergreen Hlth Rehabil Serv, Rehabil Med, Kirkland, WA USA
[5] Cleveland Clin, Dept Neurol, Cleveland, OH 44106 USA
[6] Case Western Reserve Univ, Coll Med, Cleveland, OH 44106 USA
[7] Swedish Neurosci Inst, Seattle, WA USA
[8] Univ Maryland, Sch Med, Dept Neurol, Baltimore, MD 21201 USA
[9] VA Maryland Hlth Care Syst, Res Serv, Baltimore, MD USA
[10] Brown Univ, Dept Neurol, Providence, RI 02912 USA
[11] Brown Univ, Dept Community Hlth, Providence, RI 02912 USA
[12] Providence VA Med Ctr, Rehabil Res & Dev Ctr Restorat & Regenerat Med, Providence, RI USA
[13] Mt Sinai Rehabil Hosp, Mandell Ctr Multiple Sclerosis, Hartford, CT USA
[14] Evergreen Neurosci Inst, Evergreen Hlth Multiple Sclerosis Ctr, Kirkland, WA USA
[15] Amer Acad Neurol, Ctr Hlth Policy, Minneapolis, MN USA
[16] Univ Kansas, Dept Neurol, Sch Med, Kansas City, KS USA
[17] Beth Israel Deaconess Med Ctr, Dept Neurol, Boston, MA 02215 USA
[18] Boston Univ, Sch Med, Dept Neurol, Boston, MA 02118 USA