> Nope, there is another important thing that matters: some of the cancers tested are really hard to detect early by other means, and very lethal when discovered late.
You are arguing for testing everyone there. If you cannot detect them by other means, you need to test for them this way. And do it for everyone. You have already set up the unrealistic wargaming scenario. You picked pancreatic cancer as your example where you do have to test every 6 months at least, because if you do it more rarely, the disease progression is so fast that testing is useless. There are no specific risk groups for pancreatic cancer beyond a slight risk increase by "the usual all-cancer risk factors". Nothing to pick a test group by.
And a 99% overall false positive rate is easy to achieve, lot's of tests that are in use have this property if you just test everyone very frequently. Each instance of testing has an inherent risk of being a false positive, and if you repeat that for each person, their personal false-positive risk of course goes up with it. All tests that are used frequently have an asymptotic 100% false positive rate.
Are you mistaking me for someone else? I never said or even implied that.
"And a 99% overall false positive rate is easy to achieve,"
Not in the real world, any such experiment will be shut down long before the asymptotic behavior kicks in. Real healthcare does not have unlimited resources to play such games. That is why I don't want to wargame them, it is "Luxembourg attacks the US scenario".
"There are no specific risk groups for pancreatic cancer"
This is just incorrect, people with chronic pancreatitis have massively increased risk of developing pancreatic cancer (16x IIRC). There also seems to be a hereditary factor.
Czech healthcare system, in fact, has a limited pancreatic cancer screening program since 2024, for people who were identified as high-risk.
You are arguing for testing everyone there. If you cannot detect them by other means, you need to test for them this way. And do it for everyone. You have already set up the unrealistic wargaming scenario. You picked pancreatic cancer as your example where you do have to test every 6 months at least, because if you do it more rarely, the disease progression is so fast that testing is useless. There are no specific risk groups for pancreatic cancer beyond a slight risk increase by "the usual all-cancer risk factors". Nothing to pick a test group by.
And a 99% overall false positive rate is easy to achieve, lot's of tests that are in use have this property if you just test everyone very frequently. Each instance of testing has an inherent risk of being a false positive, and if you repeat that for each person, their personal false-positive risk of course goes up with it. All tests that are used frequently have an asymptotic 100% false positive rate.