From "Talk of the Nation: Science Friday":

IRA FLATOW: Up next, when medicine can become too much of a good thing. Is your health care killing you? In her new book, my next guest argues that our health care system delivers a lot of care that we really don't need. It does not improve the health of patients. A lot of it is based on, not on sound science. In some cases, it might actually leave patients worse off than they started. So in a system where some people are getting no health care, other people are getting too much. How can we find the balance? Joining me now to talk more about it is my guest, Shannon Brownlee, medical writer and a Schwartz Senior Fellow at the New America Foundation. Her new book is called Overtreated: Why Too Much Medicine is Making Us Sicker and Poorer. ...

What made you decide to write something like this?

Ms. BROWNLEE: Well, I've been writing about medicine for more than 20 years, I hate to admit that. That tells me I'm older than 25. And the more I wrote stories about sort of how medicine was going to save us from this death in the other disease, the more I started realizing that a lot of what I was writing about didn't have very good evidence behind it. And one story in particular sort of struck me. It was the story of a very painful and ultimately useless treatment called high-dose chemotherapy for breast cancer. And in writing this story, when I - or reporting this story when I was at US News & World Report, I started realizing there was lot of medicine that didn't have - didn't have valid science behind it, and that just stunned me. So I got interested in sort of how this medicine really works and how do we decide what we pay for, and how the doctors decide what they're going to do.

FLATOW: So you - are you saying that a lot of medicine is just ideas handed down from generation to generation without scientific backing?

Ms. BROWNLEE: Yes.

FLATOW: That it actually works.

Ms. BROWNLEE: Yes, that's exactly what I'm saying. And it seems kind of stunning - it's the 20th century. We've had these incredible gains in life expectancy and we have all these amazing, high-tech kinds of tools that we see physicians being able to use, and many of them are quite miraculous and real breakthroughs. But an enormous amount of medicine is not based in science. In fact, the Institute of Medicine estimates that maybe half of what physicians do has valid evidence to back it up. And another expert named David Eddy, in medical evidence, says he thinks it's about 15 percent. ...

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