RT Journal Article SR Electronic T1 Clinical trials registry JF Canadian Medical Association Journal JO CMAJ FD Canadian Medical Association SP 980 OP 980-a DO 10.1503/cmaj.1041673 VO 172 IS 8 A1 L. John Hoffer A1 Jack Mendelson YR 2005 UL http://www.cmaj.ca/content/172/8/980.2.abstract