Mammograms and Our Perception of Risk
In the heated debate over the new routine mammogram screening recommendations from the U.S. Preventive Services Task Force, not enough coverage has focused on our perception of risk.
It's important context for all reporting on medical screening.
What a golden opportunity has been missed to educate Americans about the implications of their health care choices. Otis W. Brawley, the chief medical officer of the American Cancer Society, in an op-ed in today's Washington Post condemning the USPSTF guidelines, confirms that mass screening would only save at a maximum 600 out of the 4,000 women under 50 who die of breast cancer annually. What he failed to point out is that 1.14 million American women would have to be screened annually for ten years to achieve that goal...
...Health care is complex. Most treatments that "work" only work in a fraction of the people who get that treatment. Each has risks, which also affect a subset of those treated. Evaluating value is a trade-off between risks and benefits. Because breast cancer is such a high profile issue, the new mammography guidelines offered the Obama administration a chance to educate the public about the trade-offs involved in making those choices, and how the nation might wring more value out of the money it spends on health care.
Paul Waldman, writing in the American Prospect, spells out the dilemma for journalists:
The controversy also demonstrates how difficult it is to have a reasoned discussion and make good policy when scientific claims based on aggregates of cases are put up against vivid anecdotes from individual people.
Unsurprisingly, news reports about this issue have been filled with women testifying about the success of their own pre-50 mammograms. Since reporters always look for ordinary folks who can embody a controversy, they'll gravitate toward those who can say, "If I hadn't had a mammogram when I was 41, I'd be dead." The other side will be represented by a scientist wielding a stack of studies and figures.
And this HCIT Industry News blog post on risk is also worth a read. Finally, you should also get a copy of "Risk: A Practical Guide for Deciding What's Really Safe and What's Really Dangerous in the World Around You," by David Ropeik (a great interview on these issues) and George Gray, which engagingly spells out why we humans have such a hard time perceiving health risks accurately. It offers excellent background on the debate over various types of medical screenings, not just mammograms.