It is reasonable to demand from a screening test that it leads to better outcomes for those who are screened. The strongest claim I have ever seen for any cancer screen is “this test reduces the risk that you will die of Cancer X.” Numbers needed to screen are in the high hundreds. Have we ever seen a trial of a test that reduces all-cau…
It is reasonable to demand from a screening test that it leads to better outcomes for those who are screened. The strongest claim I have ever seen for any cancer screen is “this test reduces the risk that you will die of Cancer X.” Numbers needed to screen are in the high hundreds. Have we ever seen a trial of a test that reduces all-cause mortality? (I have not; please correct me if I missed it.) The initial data from the NLST suggested that this was (surprisingly) the case, but that claim was not supported with longer term follow up.
Until we have such a trial, we should not use terms like “life-saving” for any screening test. Unfortunately, that language is prominent in the article by Dr. Matthew Hobbs that is linked from your current dialogue. (https://prostatecanceruk.org/about-us/news-and-views/2022/04/why-don-t-we-invite-all-men-for-a-prostate-cancer-test) The article claims that "Clinical trials have shown us that using the PSA test to identify prostate cancer can save lives.” Its graphic claims that a project to invite men to get a PSA dropped prostate cancer deaths from 88 to 71, and uncritically equates this to 17 lives saved.
Your dialogue offers the Hobbs paper as the best current attempt to quantitate all potential effects of screening. Hobbs indeed attempts to describe the harms from screening, but overstates the benefits.
It is reasonable to demand from a screening test that it leads to better outcomes for those who are screened. The strongest claim I have ever seen for any cancer screen is “this test reduces the risk that you will die of Cancer X.” Numbers needed to screen are in the high hundreds. Have we ever seen a trial of a test that reduces all-cause mortality? (I have not; please correct me if I missed it.) The initial data from the NLST suggested that this was (surprisingly) the case, but that claim was not supported with longer term follow up.
Until we have such a trial, we should not use terms like “life-saving” for any screening test. Unfortunately, that language is prominent in the article by Dr. Matthew Hobbs that is linked from your current dialogue. (https://prostatecanceruk.org/about-us/news-and-views/2022/04/why-don-t-we-invite-all-men-for-a-prostate-cancer-test) The article claims that "Clinical trials have shown us that using the PSA test to identify prostate cancer can save lives.” Its graphic claims that a project to invite men to get a PSA dropped prostate cancer deaths from 88 to 71, and uncritically equates this to 17 lives saved.
Your dialogue offers the Hobbs paper as the best current attempt to quantitate all potential effects of screening. Hobbs indeed attempts to describe the harms from screening, but overstates the benefits.