RT Journal Article SR Electronic T1 Sophia JF Emergency Medicine Journal JO Emerg Med J FD BMJ Publishing Group Ltd and the British Association for Accident & Emergency Medicine SP 842 OP 842 DO 10.1136/emj.2009.085308 VO 26 IS 11 YR 2009 UL http://emj.bmj.com/content/26/11/842.abstract AB