Map of life expectancy at birth from Global Education Project.

Monday, August 06, 2012

Just in case you still give to Susan G. Komen . . .


. . . one more reason to send your money elsewhere. This is from Steven Woloshin and Lisa Schwartz at Dartmouth, who review Komen's advertising urging women to get screening mammograms. "Komen's public advertising gives women no sense that screening is a close call. Instead, it simply tells women to be screened, overstates the benefits of mammography, and ignores harms altogether."

They specifically critique an ad that claims that "early detection saves lives. The 5-year survival rate for breast cancer when caught early is 98%. When it's not? 23%."

I know my readers are smart enough to see right away what is wrong with this assertion. It's called lead time bias. Suppose you could has a time machine, and you first  identified a group of 100 women who died of breast cancer at age 70. Then you went back in time and gave half of them a mammogram at age 65. The other half would have been diagnosed later, when their tumor became palpable. The ones who got screened would have five year survival of 100%; the ones who did not, would have five year survival of 0%. That's a big difference, but it's completely meaningless, except that the screened women had three or four years more to be sick and undergoing surgery and chemotherapy.

The best available estimate we have now is that mammographic screening reduces the chance that a women in her 50s will die of breast cancer within 10 years from .53% to .46%. When I do the math, that tells me that 7 women out of 10,000 will will avoid this fate.

For each of them, anywhere from 2 to 10 women will be overdiagnosed -- will be diagnosed with a condition that, if left untreated, would never have harmed them. They will undergo surgery, radiation, and/or chemotherapy, which does them no good, and only harms them.

So why does the Komen Foundation lie to women? I'm going to take a guess -- some of their big donors profit from cancer treatment. If they want to argue with me, my e-mail is in the side bar.

2 comments:

Anonymous said...

Mr Woloshin and Ms Schwartz, I don't wish to argue with you because I believe that noone should lie. I feel there is no reason for it. However, you would have to agree that the Susan G Komen organization has brought breast cancer to become a common and known cancer. They have raised many dollars for cancer research and public education. It may true that their biggest donors benefit but I think it also has done good for the public worldwide. Research has advanced and early detection does help. Those who do live longer don't always live with pain and suffering, but are thankful for each and every moment they are alive. Everyone has the chance to be one of the seven people out of the 10,000 to aviod the fate of death by breast cancer. Wouldn't you be happy if it where you or a loved one? I believe you would give to the Susan G Komen orgainzation if it meant you could survive.

Danny said...

Susan G. Komen for the Cure, formerly known as The Susan G. Komen Breast Cancer Foundation, often referred to as simply Komen, is the most widely known, largest and best-funded breast cancer organization in the United States.

Regards,
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