[1] Stanford Univ, VA Palo Alto Hlth Econ Resource Ctr, Menlo Pk, CA 94025 USA
[2] Stanford Univ, Dept Hlth Res & Policy, Menlo Pk, CA 94025 USA
[3] Brown Univ, Providence Vet Adm Med Ctr, Neurol Sect, Providence, RI 02912 USA
[4] Yale Univ, Sch Publ Hlth, Vet Adm Connecticut Cooperat Studies Program Coor, New Haven, CT USA
[5] Indianapolis Vet Adm Med Ctr, Indianapolis, IN USA
[6] Indiana Univ Sch Med, Indianapolis, IN USA
[7] Vet Affairs Off Res & Dev, Cooperat Studies Program Cent Off, Washington, DC USA
[8] MIT, Dept Mech Engn, Cambridge, MA 02139 USA
[9] Univ New Mexico, Vet Affairs Cooperat Studies Program Clin Res Pha, Albuquerque, NM 87131 USA
[10] Vet Affairs Connecticut Healthcare Syst, Dept Med, West Haven, CT USA
[11] Univ Florida, N Florida S Georgia Vet Hlth Syst, Gainesville, FL USA
[12] Univ Florida, Occupat Therapy Dept, Gainesville, FL USA
[13] Univ Washington, Vet Affairs Puget Sound Hlth Care Syst, Seattle, WA 98195 USA
[14] Univ Maryland, Baltimore Vet Affairs Med Ctr, Baltimore, MD 21201 USA
[15] Cornell Univ, Dept Neurol & Neurosci, Weill Med Coll, White Plains, NY USA
[16] Vet Affairs Maryland Hlth Care Syst, Neurol Serv, Baltimore, MD USA
[17] Vet Affairs Maryland Hlth Care Syst, Res Serv, Baltimore, MD USA
[18] Duke Univ, Dept Community & Family Med, Durham, NC USA
[19] Vet Affairs Palo Alto Hlth Econ Resource Ctr, Palo Alto, CA USA
[20] Cooperat Studies Coordinating Ctr, West Haven, CT USA