Controversy continues over the mammography guidelines released last week by the U.S. Preventive Services Task Force. As family physicians and preventive medicine specialists who have worked with the task force in many capacities over the years, we'd like to dispel some myths about the panel and try to put the recommendations into context.

First, the myths.

The task force members are not government bureaucrats. They are doctors, nurses and methodologists from universities, health systems and public health agencies who are experts in assessing preventive services.

Although appointed by the U.S. Agency for Healthcare Research and Quality (as required by Congress), the panel is independent. It does not speak for the government or dictate health insurance coverage policies. The panel sets its own agenda and has been working on breast cancer screening recommendations for two years. That the mammography recommendations were announced during the debate on health reform is a coincidence.

The task force recommendations are not related to costs, saving money or rationing care. The panel did not consider monetary costs when reviewing evidence. The sole concern was weighing the balance of health benefits and harms of different strategies of screening to determine what is best for women's health.

No one disputes the science behind the recommendations. Mammography has been proven effective in reducing deaths from breast cancer in women ages 40 to 74. All screening tests, however, involve a trade-off between benefits and harms. In younger women a lot more screening is needed to save one life because breast cancer is less common in younger women and abnormalities are harder to spot on X-rays. About 1,900 women need to be screened to prevent one breast cancer death in women ages 39 to 49, as opposed to only 377 women ages 60 to 69. That means many more overdiagnoses and false-positive results in women under 50, with the accompanying harmful side effects: unnecessary biopsies and surgeries, more X-rays and more anxiety.

There is no magic age at which the benefits of screening absolutely outweigh the harms. It is a continuum. Women of all ages should weigh the pros and cons of mammography. The task force considered this a close call, particularly for women under age 50, for whom the harms may outweigh the benefits. The panel recommended against routine screening of all women under 50, saying that the decision to undergo or defer screening should be made by women after discussing the benefits and risks with their doctors.

We think women should ignore the political furor surrounding these recommendations. This is not a government plot to save money. No one wants insurance companies to deny coverage for mammograms. The task force is saying that the greatest benefit from screening mammography occurs for women ages 50 to 74. The task force is not against women getting mammograms in their 40s. The panel simply wants women in that age group and older women to discuss the risks and benefits with their doctors before they get tested. No one should be against that.