[somewhereoutth]

No.

When there is low prevalence of a condition, but a non-zero false positive rate of a test, the false positives generated by universal testing can in fact be a net dis-benefit (worry, invasive further procedures, etc) to the patient population as a whole, regardless of cost. This is a well understood statistical phenomenon, and is carefully considered by healthcare systems when advising on testing.

[mgraczyk]

Read my #2 option, which accounts for that

[lucianbr]

As if there was an easy, foolproof and precise way to calculate these probabilities. "Just only alter the patient when it is appropriate" he said. You can solve all the world's problems this way, just "always do the right thing". Reality, unfortunately, is more complicated.

What if in reality the doctors can only say if the probability is above 60% or not? What if some doctors are better than others at estimating probabilities? What if estimates are influenced by financial reasons by some entity like the hospital or insurer?