RT Journal Article SR Electronic T1 Levels of evidence JF Neurology JO Neurology FD Lippincott Williams & Wilkins SP 8 OP 10 DO 10.1212/01.wnl.0000342200.58823.6a VO 72 IS 1 A1 Gross, Robert A. A1 Johnston, Karen C. YR 2009 UL http://n.neurology.org/content/72/1/8.abstract AB