Paul Alper writes:
You recently posted ongraphs and how to convey information. I don’t believe you have ever posted anything on this dynamite randomized clinical trial of 90,000 (!!) 40-59 year-old women over a 25-year period (also !!). The graphs below are figures 2, 3 and 4 respectively, ofThe control was physical exam only and the treatment was physical exam plus mammography.The graph clearly shows that mammography adds virtually nothing to survival and if anything, decreases survival (and increases cost and provides unnecessary treatment). Note the superfluousness of the p-values.There is an accompanying editorial in the BMJwhich refers to “vested interests” which can override any statistics, no matter how striking:
We agree with Miller and colleagues that “the rationale for screening by mammography be urgently reassessed by policy makers.” As time goes by we do indeed need more efficient mechanisms to reconsider priorities and recommendations for mammography screening and other medical interventions. This is not an easy task, because governments, research funders, scientists, and medical practitioners may have vested interests in continuing activities that are well established.
And for the aging males in your audience:Nevertheless, the UK National Screening Committee does recommend mammography screening for breast cancer but not prostate specific antigen screening for prostate cancer.Because the scientific rationale to recommend screening or not does not differ noticeably between breast and prostate cancer, political pressure and beliefs might have a role.
Pretty amazing that the effect is 0. That’s hard to believe! Although I guess the point is that a thorough physical exam won’t miss much.