[DanBC]

> Hopefully get other tests done, to confirm diagnosis

Those other tests involve things like "needle biopsy" -- they shove a needle through your chest into your lung into the suspect tissue to get a sample. This carries risk. We can justify that risk if it saves life. But this is the problem with screening -- often it doesn't save life (of course, it depends on the type of screening).

https://www.radiologyinfo.org/en/info.cfm?pg=nlungbiop

> Having more information should never make you more wrong

But you can see how having lots of low-quality information could make someone more wrong -- these are not clear signals, because if they were it wouldn't be a problem. These are almost noise. We're taking data from a large population ("4 in 100 people with this result have this disease") and trying to apply it to the individual, and when we try to get more information we subject this person to more radiation in scans or invasive procedures or both. We increasing the risk, but not necessarily saving life.

> there's no point of doing them if that risk outweighs the expected value of evidence gathered

Yes, this is exactly the balance that doctors are making. They're looking at all cause mortality and seeing if life is saved.