RT Journal Article SR Electronic T1 Trial registration: must take place before or at the onset of enrolment JF Emergency Medicine Journal JO Emerg Med J FD BMJ Publishing Group Ltd and the British Association for Accident & Emergency Medicine SP 176 OP 176 DO 10.1136/emermed-2014-203566 VO 31 IS 3 A1 Goodacre, Steve YR 2014 UL http://emj.bmj.com/content/31/3/176.abstract AB