It's official: Mammograms save lives.
That's the finding of a major new study which shows New Zealand's breast screening programme has delivered clear and significant reductions in breast cancer deaths.
The study, commissioned by BreastScreen Aotearoa (BSA), reveals that women who have had their breasts checked have a 39 percent lower breast cancer death rate than those who have never been screened.
The death rate is even lower among women who regularly take part in the national breast screening programme for women aged 45 to 69.
The results are similar to those seen in mortality studies of overseas breast screening programmes.
The report, Cohort and Case Control Analyses of Breast Cancer Mortality, delivered some bad news too, confirming previous findings that Maori women have higher rates of both developing and dying of breast cancer.
On top of this, Maori women are less likely to get screened than other New Zealand women, BSA clinical leader Dr Marli Gregory said.
"However, this study confirms that if we can achieve the same participation rates for Maori women as for the rest of the population, we would see similar reductions in the rate of deaths from breast cancer," Dr Gregory said.
"This is why it is important for Maori women to take part in organised breast screening."
The BSA commissioned the University of NSW to do the mortality evaluation using data on all women who were eligible for breast screening from 1999 to 2011.
The New Zealand Breast Cancer Foundation welcomed the report as hard evidence that mammograms save lives.
"It's time for all those people who have sought to undermine our valuable breast screening programme to finally shut up," said the foundation's chief executive Evangelia Henderson.
"BSA does an amazing job, and it's very frustrating when irrelevant overseas studies, particularly from countries like America, which simply doesn't have a national, co-ordinated screening programme, are used to claim that mammograms aren't effective."
The foundation recommends that women consider annual mammograms from age 40-49, then have two-yearly mammograms from age 50.