RT Journal Article SR Electronic T1 Correction JF Journal of Neurology, Neurosurgery & Psychiatry JO J Neurol Neurosurg Psychiatry FD BMJ Publishing Group Ltd SP 763 OP 763 DO 10.1136/jnnp.45.8.763 VO 45 IS 8 YR 1982 UL http://jnnp.bmj.com/content/45/8/763.1.abstract AB