Mammography screening programs lower death rates

The paper has reignited debate between oncology and public health experts about the benefits and harms of screening programs for breast cancer.

A media release from the BMJ initially suggests that “this study largely confirms what is already known – that the benefits of breast screening are modest at best”. However, later in the same release, the authors of the study are quoted as saying the results “indicate a substantial effect” of screening. 

The study involved all women in Norway aged 50–70 between 1986 and 2009 when a national screening program was being rolled out by the Norwegian Cancer Registry, which also collects mandatory reports of all cancer-related deaths.

Previous trials in the 1970s and 1980s into the efficacy of breast cancer screening have been criticised for comparing deaths between women who took up screening and women who did not because such results could be biased by a healthy volunteer