By Rhoda Baer (Photographer)
[Public domain or Public domain],
via Wikimedia Commons
You know the old expression, “Don’t blog angry,” right?

Blew it.

On my way in to work this morning, I heard a story about the stunning cost of false positives of mammography.

Some good information here: 700,000 women’s cases (aged 40-59) were studied. 11% were called back based on the results of their mammograms. 98.6% of those turned out to be false positives. This costs billions. Then, some indolent cancers are found and treated like they were life-threatening. More billions.

Plus stress. Plus side effects. Plus the cascading unintended consequences.

At this point in the story, I am happy that we’re talking about this, rather than deferring to fear-based marketing about the wonders of mammography and early detection.

Then they close with a counterpoint from a doctor who says these costs are overstated. I’d argue that they are understated because you can’t put a dollar value on a lot of this. And he said that mammography is the best screening tool we have. I might agree with that, although I wish he would have said that it’s not good enough.

The report closed with a statement that this doctor says mammograms reduce deaths from breast cancer by 20%

What the hell???

THEN I got to work, logged into the website and the opening line of the article says: “There’s no question mammograms can save lives by detecting breast cancer early.”

W T F?????

Of course there are questions about that claim. Mammograms have been shown to provide a tiny benefit, at best, and mostly to older women. How do I know that?  NPR REPORTED IT.

From that article: “Mammograms don’t reduce the number of women dying from breast cancer, according to a large and long-term Canadian study.”

This is shoddy journalism.

Of course the real harm here is not my blood pressure, it’s the perpetuation of incorrect medical information.

8 thoughts on “ET TU, NPR?”

  1. If 11% of those tested were found to have ‘suspicious’ results that required further testing, does that mean that the remaining 89% had mammograms with no evidence of cancer? Or that the remaining 89% were split between a ‘clear’ group and a ‘positive for cancer’ group where no further testing was required?

    1. Hi Matt. Not 100% sure and I will do a little more research later, but I believe we are talking about screening mammograms here. They’d never be used as a diagnostic tool, just as a way to recommend further testing if needed.

      Of course, you remind me of another important point – this does not measure false negatives either, which I personally experienced several times.

      I’ll get back with you when I find an answer.


    2. Matt,

      I can’t get the full text of the study without paying $15, but the 10% call back rate seems to be pretty standard across other studies. In other words, 90% are told they are fine and about 10% are called back. Mammography is more accurate in older women because pre-menopausal women tend to have dense breast tissue that makes the films harder to read.

      Interestingly, NCI points out that mammograms have a 70%-90% sensitivity. That means up to 30% of women who have breast cancer will be told they are fine. As you know, that’s what happened to me.

      And, again, more accurate detection is dandy, but until we know how to tell which tumors are dangerous and which are indolent, unnecessary costs will mount.


      1. Diagnostic break thrus hard to come by in a system that discourages innovation and subsidizes over treatment. Headwinds for productivity improvement, tailwinds for status quo.

  2. Wow, you just pointed out such a serious flaw in reporting. Instead of showing the body of evidence and the argument, we get ‘expert’ quotes and headliners that counter either the past reporting or the information presented, or both. The majority of those tested have no evidence of cancer, and the costs (in terms of anxiety, suffering, side effects, false promises, stress, and money) of overdiagnosis and overtreatment must be taken into account. There are many interests and stakeholders in the mammography controversy; seldom does the body of evidence weigh in clearly.

    1. Yes. And I would imagine that these stories that fall into the dominant-but-not-really-all-that-true narrative rather than contradicting it are going to be assigned more weight by the general, confused public.


Comments are closed.