Today's issue of the British Medical Journal carries an article by Peter Gøtzsche and his team at the Nordic Cochrane Center in Copenhagen. This is the latest salvo in Gøtzsche's battle against the over-zealous promotion of breast screening.

In the article, he specifically attacks the leaflet issued by the British NHS Breast Screening Programme but he says 'the one-sided propaganda about breast screening is a global phenomenon'. He points out that 'it has not been proved that screening saves lives' although the leaflet claims 1400 lives are saved every year in the UK because of breast screening. However, his main criticism is not the exaggerated benefits of screening but the lack of any information about major harm:

'No mention is made of the major harm of screening — that is, unnecessary treatment of harmless lesions that would not have been identified without screening. This harm is well known and acknowledged, even among screening enthusiasts.'

My Risk Perspective

I first came across this debate in 2004. I was looking for statistics on breast cancer and I downloaded a 'factsheet' from the website of Cancer Research UK. I was surprised to find that the data presented in the leaflet did not support the claims it was making! My wife is an editor of the European Journal of Hospital Pharmacy (EJHP) and, knowing my interest, she showed me an article that had just appeared in the EJHP, which presented what I considered a very biased view in favour of screening. So, I wrote to the EJHP (letter attached below) and received positive feedback from Gøtzsche.

In today's BMJ, Gøtzsche writes:

'We believe that if policy makers had had the knowledge we now have when they decided to introduce screening about 20 years ago... we probably would not have had mammography screening.'

This is the fascinating thing from a risk perspective. When we become committed to a cause, we need stronger evidence to convince us to abandon the cause than we needed to take up the cause in the first place. When a dedicated doctor has given years of her life to breast screening, it's very difficult to persuade her that it may not be very effective.