Re-examination of data from four large studies of the benefits and harms of mammography screening shows that the benefits are more consistent across these studies than previously understood and that all the studies indicate a substantial reduction in breast cancer mortality with screening, according to results presented at the 2013 San Antonio Breast Cancer Symposium ( SABCS ), held Dec. 10–14.

There is widespread debate in academic literature and the media about the absolute benefit of mammography screening, commonly defined as the number of women who must be screened to prevent one breast cancer death. Four major reviews of screening and mortality each paint a different picture, with estimates of the number of women who must be screened ranging from 111 to 2,000, an almost twentyfold difference.

Read more here