RT Journal Article SR Electronic T1 BET 1 JF Emergency Medicine Journal JO Emerg Med J FD BMJ Publishing Group Ltd and the British Association for Accident & Emergency Medicine SP 141 OP 142 DO 10.1136/emj.2009.088211a VO 27 IS 2 YR 2010 UL http://emj.bmj.com/content/27/2/141.2.abstract AB