[1] Univ Rochester, Sch Med & Dent, Dept Neurol, Rochester, NY 14620 USA
[2] Univ Rochester, Sch Med & Dent, Dept Community & Prevent Med, Rochester, NY 14620 USA
[3] Univ Colorado, Hlth Sci Ctr, Dept Neurol, Denver, CO 80262 USA
[4] Dartmouth Hitchcock Med Ctr, Neurol Sect, Lebanon, NH 03766 USA
[5] Amer Acad Neurol, St Paul, MN USA