In recommending “against routine screening mammography in women aged 40 to 49 years,” the U.S. Preventive Services Task Force is clearly weighing potential lives saved against the money needed to save them.
The task force recommended against screening because it concluded that there was “moderate evidence that the net benefit [of screening mammograms] is small for women aged 40 to 49 years.” The documents supporting its decision review selected literature on mammography and breast cancer survival. They show that mammography reduces the risk that women aged 40 to 49 will die from breast cancer about as much as it reduces the risk that women aged 50 to 59 will die from breast cancer. According to one of the supporting papers, screening produces a 15% reduction in breast cancer mortality in both groups.
What are the costs that the Task Force measured against the benefit of a 15% reduction in mortality in order to come up with its “small net benefit?” No one knows because they don’t say.
Radiation risks are said to be very low and the pain and anxiety associated with the procedure are manageable for most people. Overall, the Task Force’s supporting papers say that adequate evidence suggests that the overall harms associated with mammography are moderate for every age group considered, but that “false-positive results are more common for women aged 40 to 49 years.” How much do the false positives cost? It doesn’t say.
Nonetheless, one can infer that the false positives are the real reason for the Task Force recommendations. One of its references, a paper in the Annuals of Internal Medicine, reports on the results of 6 models that estimate the outcomes of breast cancer using various assumptions. That paper states that:
If the goal of a national screening program is to reduce mortality in the most efficient manner, then programs that screen biennially from age 50 years to age 69, 74, or 79 years are among the most efficient on the basis of the ratio of benefits to the number of screening examinations. If the goal of a screening program is to efficiently maximize the number of life-years gained, then the preferred strategy would be to screen biennially starting at age 40 years. Decisions about the best starting and stopping ages also depend on tolerance for false-positive results and rates of overdiagnosis.
In other words, to save the most lives, you screen the 40 to 49 year olds. To save money by getting rid of pesky false-positives that require follow-up visits, you don’t. Medical researchers have long known that the cost of screening per life saved is lower for women in their 50s than for women in their 40s. But should money be the determining factor?
The main difference between U.S. health care and health care of other developed countries is that the U.S. is concerned with saving lives. Other countries are more likely to balance medical benefits against economic costs. That is why U.S. women get more Pap smears and more mammograms, and have better cancer survival rates.
As health reform legislation wends its way through Congress, two things are worth keeping in mind: (1) The federal government will determine what kind of health insurance everyone must have, including such screening benefits as mammograms and Pap smears, and (2) 15 years ago what helped kill health reform was Hillary Clinton’s decision to mandate from the White House which women would be eligible for such tests and at what age and how often.