RT Journal Article SR Electronic T1 BET 1: Predicting the need for knee radiography in the emergency department: Ottawa or Pittsburgh rule? JF Emergency Medicine Journal JO Emerg Med J FD BMJ Publishing Group Ltd and the British Association for Accident & Emergency Medicine SP 77 OP 78 DO 10.1136/emermed-2011-200980 VO 29 IS 1 YR 2012 UL http://emj.bmj.com/content/29/1/77.2.abstract AB