The criticisms of the mammogram study are valid

2/26/2014 01:37:00 PM
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The new study shows that training people to feel for lumps is as effective as universal mammogram screenings. Given that, the former should be strictly prefered because it is cheaper, minimal-risk, and just as effective.
...but we need to act on the evicence we have.

Aaron Carroll reminds me of the people who were unconvinced by the latest mammogram study that showed, basically, that detecting breast cancer before a noticeable lump exists has no value-added. In post after post, Carroll responded to various criticisms of the mammogram study that argued, for example, that the technology in that study was two decades old, and thus the results are not generalizeable to today. As Carroll points out, that critique can always be applied to pretty much any large long-term study in medicine; the critique is technically valid, but not a good reason for ignoring the evidence.

It's very true that we are in the process of researching and improving treatment options for breast cancer, and thus what is true about early detection with mammograms today might not be true in the near future. There's no way to know. But there's a right way and a wrong way to handle that uncertainty.

The right way is to demand more mammogram studies, while recommending against universal mammogram screenings in the meantime. Mammogram screenings represent more than minimal risk to patients: even ignoring the substantial economic costs (resources that could have been used more productively), they lead to more biopsies and other proceedures in women who do not have cancer, which can cause serious complications in a small fraction of people[*] that should not be ignored in the cost-benefit calculus.

The wrong way to handle this uncertainty is to continue to advocate universal mammogram screening inspite of the fact that the evidence says they do more harm than good.

That's not to say that no one should get mammograms until further notice. People in particularly high-risk subgroups, such as women in families with high rates of breast cancer, should probably still get regular screenings. And generally the first thing you'll do after feeling a lump in the breast is get a mammogram, which may also be a good idea. But, a healthy 40 year old woman with no prior breast cancer risks should not be getting mammograms, until further notice.

[*]I use the gender neutral "people" instead of "women" because breast cancer also occurs in men. Sometimes, mammograms are also performed on men, though this is less common because it tends to be more painful and has less chance of detecting cancer than it does for women.
Anonymous 2/28/2014 12:51:00 AM
No, we don't need "to demand more mammogram studies" we need to demand for the public to get informed about the real facts of mammography instead of the whitewashed, biased version of the facts amicable to the interests of the medical profession (read The Mammogram Myth by Rolf Hefti).

The actual scientific data shows irrefutably that this test does more harm than good. More studies is just a waste of money and time, and will lead to more damage to unsuspecting women.
Matthew Martin 2/28/2014 04:15:00 PM
"The actual scientific data shows irrefutably that this test does more harm than good."
This is true, except you left out a crucial caveat: that data only shows that *so far* early detection with mammograms does more harm than good. There's no reason to believe it will remain this way for ever. As treatments for breast cancer become more effective and less invasive, I'd say that it's likely that someday in the future, mammograms will become net-beneficial because of improvements in early cancer treatments.

So we should recommend against universal screenings right now, but we still need to continually update our data on mammogram effectiveness as cancer treatments change.