RT Journal Article SR Electronic T1 What kind of randomized trials do we need? JF Canadian Medical Association Journal JO CMAJ FD Canadian Medical Association DO 10.1503/cmaj.082007 A1 Zwarenstein, Merrick A1 Treweek, Shaun YR 2009 UL http://www.cmaj.ca/content/early/2009/04/16/cmaj.082007.abstract AB