Canadian breast cancer guidelines: have they made a difference?

Background: A principal objective of the Canadian Clinical Practice Guidelines for the Care and Treatment of Breast Cancer was to reduce the variation in the way that breast cancer was being treated. To evaluate whether this goal has been reached, we examined variations among surgeons for 4 measures of surgical care and tested for differences in province-wide rates and in variations among surgeons before and after the guidelines were released.

Methods: We studied a population-based cohort of 7022 women living in Manitoba in whom breast cancer was diagnosed from 1995 to 2003 inclusive.