Wednesday, October 21, 2009
200 will have false positives, with resulting worries and potentially mutilating surgeries
10 will be diagnosed but their outcomes are the same whether they were screened or not. Likely, they all feel they were helped, even though data shows their outcomes are neutral.
1 will have her life prolonged
Overall, 200 women are harmed for every one that is helped. I think your opinion on the benefit of screening depends on whether you are one of the 200 or the 1 (or think you are the 1).
Is it worth harming 200 women to help 1? That's the question.
Screening is a value judgment. How many people is it ok to harm to help the one?
The American Cancer Society, which has long advocated early cancer screening, is rethinking its message, according to The New York Times. Spurred in part by the new analysis, the cancer society is working on a message — to put on its Web site early next year — to emphasize that screening for breast and prostate cancer and certain other cancers can come with a real risk of overtreating many small cancers while missing cancers that are deadly.