> 1) Medical tests have four quadrants--not 2. The accurate quadrants are "positive test--positive diagnosis" and "negative test--negative diagnosis". The probl

> 1) Medical tests have four quadrants--not 2. The accurate quadrants are "positive test--positive diagnosis" and "negative test--negative diagnosis". The problem quadrants are "positive test--negative diagnosis" and "negative test--positive diagnosis". The solution to false positives is not "let's not test and bury our heads in the sand". The solution to false positives is to test a lot more to monitor the progression of disease. > Biopsies can result in infections ... If you are testing a lot of people and the disease is relatively rare, you may kill more people with false positives than the disease itself This is junk science. People troll through records looking for correlations and publish when they find them. Many prospective studies show that biopsies don't increase mortality rates. > A negative test with a positive diagnosis is problematic because people will tend to blow off other signs since "the test was negative". This can delay lifesaving treatment. If you have symptoms you will be given a test anyway. So you need to deal with base rates, false positives, etc, regardless. > 2) The body often clears a lot of diseases. Lumps that could be cancerous often disappear. Swellings come and go. Viruses do more and varied damage than we originally thought. The body repairs itself and reversion to the mean is a thing. So the solution is to monitor them constantly. > 3) Diseases may not even be that problematic. Sure, aggressive prostate cancer is an issue. However, practically every single man will eventually get prostate cancer. Most men die of something else before prostate cancer is an issue. Is it worth risking becoming incontinent or impotent from a prostate cancer treatment? Yup. I said that above. The problem is that without universal screening we don't know anything about which cancers are going to be a problem and which are not. And we don't have data to target drugs and interventions. The solution is to have universal screening and regular followups, then use the data to narrow down who needs treatment. > 4) Will the positive test even lead to a correct request for treatment? People demand antibiotics for viral infections all the time. My body never gets rid of strep throat, so I will force my doctor to give me a quick strep test when I have a persistent sore throat. The first time I did this my doctor was literally stunned when I simply thanked him and got ready to walk out since the test came back negative. Everyone else will demand antibiotics even if the test is negative. You can demand whatever you want. What does that have to do with anything?