A recently published study from the Hugh Adam Cancer Epidemiology Unit of the Department of Preventive and Social Medicine at the University of Otago Dunedin School of Medicine has estimated breast screening from the age 50-69 could result in between 20 and 34 fewer deaths, and the earlier screening for 45-50-year-olds could prevent from one to seven deaths a year.
Author of the study Prof Cox said it assessed the impact of screening in New Zealand using results obtained from randomised trials of screening.
The estimates are based on a more than 80% participation rate in screening by eligible women, but at present only 61.2% of women aged 50-69 are taking part.
The lower participation rate meant fewer lives were being saved.
Only three-quarters of the estimated possible reduction would be achieved.
Prof Cox said the level of reduction in deaths would also be something which would happen over about 10 years.
The New Zealand programme had been going about that long, although not for all age groups.
Work needed to be done to increase participation in the free service.
"I don't want to sound critical of the programme, but we could do better. Other countries have."
Prof Cox said looking at the way Canterbury carried out screening would be good start.
It had a high participation rate including that from Maori. Other providers could look at what they were doing and see what was transferable and what was not.
One of the known factors which lowered the rate of repeat screenings for some women was that they found it especially uncomfortable.
Others might not like participating in any service which was seen to be associated with a hospital, as some people still saw hospitals as "places where you die.
Why go there when you are feeling well?"About 600 women die from breast cancer in New Zealand every year.
Free mammograms are provided through the screening programme for women aged 45-69.
