TY - JOUR T1 - Registration of observational studies: Is it time? JF - Canadian Medical Association Journal JO - CMAJ SP - 1638 LP - 1642 DO - 10.1503/cmaj.092252 VL - 182 IS - 15 AU - Rebecca J. Williams AU - Tony Tse AU - William R. Harlan AU - Deborah A. Zarin Y1 - 2010/10/19 UR - http://www.cmaj.ca/content/182/15/1638.abstract N2 - ER -