RT Journal Article SR Electronic T1 BET 3 JF Emergency Medicine Journal JO Emerg Med J FD BMJ Publishing Group Ltd and the British Association for Accident & Emergency Medicine SP 144 OP 145 DO 10.1136/emj.2009.088211c VO 27 IS 2 YR 2010 UL http://emj.bmj.com/content/27/2/144.abstract AB