Cunningham et al. BMC Cancer 2010, 10:674 http://www.biomedcentral.com/1471-2407/10/674 and European/Other women at any one point in time, and diverging trends over time, provide a chance for research that can provide new insights into the aetiology of breast cancer. Moreover, such insights may contribute to reducing the burden of breast cancer amongst Māori women. Acknowledgements Funding CancerTrends is primarily funded by the Health Research Council of New Zealand and the Ministry of Health as part of the Health Inequalities Research Programme. Statistics New Zealand Security Statement Access to the data used in this study was provided by Statistics New Zealand in a secure environment designed to give effect to the confidentiality provisions of the Statistics Act 1975. The results in this study and any errors contained therein are those of the author, not Statistics New Zealand. Authors’ contributions CS and TB were responsible for the inception and design of the study. 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