I’m amazed by the coverage of the newly-officially-recognised fact that screening can do harm. This article, for example, from this week’s New England Journal of Medicine: Screening Mammography and the “R” Word seems to get all flustered about the potential for women who might benefit from screening mammography ending up not having it, under new age guidelines.
For example: “The most controversial recommendation of the (US Preventative) Task Force is to delay the onset of routine screening mammography from 40 to 50 years of age. Many observers were concerned that this move away from intensive screening might signal a shift away from the war on cancer…But at a deeper level, the recommendations raise concerns about access to potentially lifesaving care. ”
There seems to be an inability to accept that screening is all about a balance of risks and trying to do as little harm for as much help as possible. It would, for example, be possible to screen every woman every six months: the problem is the multiple harms that this could do, not just overdiagnosis, but radiation exposure.
It’s also weird, because for such a consumption-based society, one might expect the consumer also to be a savvy shopper, wanting to know the pros and the cons, as well as all the different costs of a screening test. Instead, and oddly, it seems that the “doctor knows best” mentality is alive and well, no matter what the evidence says.
Additionally, there remains a judgement that preculudes patient particpiation in decision making. For example, on the risk of screening mammograms: “They include a very low risk from the radiation exposure, along with pain, anxiety, and psychological distress related to the procedure. False positive results are particularly problematic in this age group, with one study suggesting that for every case of breast cancer detected in women 40 to 49 years of age, 556 women have mammography, 47 have additional imaging, and 5 have biopsies.3 Even so, one can argue that the magnitude of the harms associated with screening seems to be modest, particularly in comparison with the benefit of a life saved. ” Isn’t that for the “consumer” to decide?
And I don’t like the way this piece describes risk either: see Cochrane for the absolute risks that are crystal clear.
Margaret McCartney
Clive Cookson
Andrew Jack