[2]
The April 2011 online edition of the Stats Can journal Health Reports contains an article reporting how, unlike several other diseases, female breast cancer in developed countries is higher among women in higher income groups. They conclude that this association with income “may be partly related to differences in parity and screening mammography, but other factors remain to be identified.”
For more details about this study, by Marilyn J. Borugian, John J. Spinelli, Zenaida Abanto, Chen Lydia Xu and Russell Wilkins, see:
Summary of key findings [3]
Full text of article in HTML [4]
News release in The Daily [5]