RT Journal Article SR Electronic T1 Emergency contraception JF Canadian Medical Association Journal JO CMAJ FD Canadian Medical Association SP E536 OP E536 DO 10.1503/cmaj.160720 VO 188 IS 17-18 A1 Diana Hsiang A1 Sheila Dunn YR 2016 UL http://www.cmaj.ca/content/188/17-18/E536.abstract