PT - JOURNAL ARTICLE ED - , TI - Query AID - 10.1503/cmaj.1040846 DP - 2004 Jun 22 TA - Canadian Medical Association Journal PG - 1992--1992 VI - 170 IP - 13 4099 - http://www.cmaj.ca/content/170/13/1992.short 4100 - http://www.cmaj.ca/content/170/13/1992.full SO - CMAJ2004 Jun 22; 170