RT Journal Article SR Electronic T1 Determining optimal catheterization rates JF Canadian Medical Association Journal JO CMAJ FD Canadian Medical Association SP 349 OP 352 DO 10.1503/cmaj.1050230 VO 174 IS 3 A1 Michelle M. Graham A1 William A. Ghali YR 2006 UL http://www.cmaj.ca/content/174/3/349.3.abstract