[nequo]

I would think that if lung cancer goes undiagnosed, it will eventually kill the patient, at which point it would be recorded as a lung cancer case. So I wouldn't expect cancer screening to bias measurement.

Would people who die from metastasized lung cancer not be recorded as having had lung cancer?

[adanto6840]

How often is an autopsy performed?

I don't know the answer but my guess is that the majority of deaths do not have an autopsy performed, especially in 65+ age range.

Edit -- I looked it up, sounds like ~7% of US deaths have an autopsy currently, so I'd guess that the data is influenced by healthcare quality (I didn't read it, perhaps they try to control for that?).