What information should be given to women invited for mammographic screening for breast cancer?

Mammography is the only proven frontline screening method for breast cancer. Following the demonstration of a reduction in breast cancer mortality with mammography, population mammographic screening services have been instituted, and there has been discussion in the medical literature of how to convey the pros and cons of screening to invited women. Much of the discussion has focused on the negative aspects of screening, such as false-positive and negative screens, overdiagnosis and anxiety. Also, some commentators have advocated rather cumbersome amounts of quantitative information. In this article we review the original evidence on the positive and negative aspects of screening, and show that the latter may have been exaggerated in the past. We suggest a few simple and clear points that should be made to the invited women, summarizing the positive and negative aspects without a mass of confusing statistics.