RT Journal Article SR Electronic T1 Free paper presentations JF Archives of Emergency Medicine JO Arch Emerg Med FD BMJ Publishing Group Ltd and the British Association for Accident & Emergency Medicine SP 81 OP 91 DO 10.1136/emj.9.1.81 VO 9 IS 1 YR 1992 UL http://emj.bmj.com/content/9/1/81.abstract AB