To clarify the Hacker News title, the article is talking specifically about prostate-specific antigen (PSA) screening, which is already known to be of uncertain medical value except in some very specific situations. As the discoverer of PSA said, "I never dreamed that my discovery four decades ago would lead to such a profit-driven public health disaster. The medical community must confront reality and stop the inapp…
From the link you posted: "last month, the American Cancer Society urged more caution in using the test" It's a very sad state of affairs when a test that unambiguously offers some statistical utility (speaking as a Bayesian, any test is useful if we do the right things with the results, this is quite literally a provable theorem of decision theory) is potentially problematic because we aren't properly evaluating wha…
Firstly, these consults are never as easy or logical in real life. If you think doctors don't understand Bayesian probabilities then how well do you think patients do?
Decision making when screen positive results occur, with appropriate perspective, is virtually impossible for patients. I've lost count of the procedures I've done for incidental findings found with screening, which we KNOW are benign and will remain benign. Unfortunately, despite very strong reassurance, patients generally want these incidentalomas removed.
Secondly, unless your positive screening test can be dealt with.... a) by a procedure that has zero risk of complications and b) in a way where no stress is engendered while waiting for definitive results and) the costs of (screening + treatment) could not be more effectively spent elsewhere ...then there will ALWAYS be negative sequelae with screening. Therefore these negatives need to be assessed in a real world RCT of sufficient size and with maximal control of bias, to make sure they don't outweigh the positives.
Your perfect world of logical patients balancing pre- and post-test probabilities, and acting accordingly doesn't exist.