Impossible to draw any conclusions from such a convoluted and problematic model. No mention of how they determined patients were unique, or whether multiple scans were counted for a single patient. No mention of patient data - seems that covariates were estimated, leading to greater uncertainty. For example, we have no idea if any of these patients already had cancer before getting a scan. And of course, this entire model is incapable of answering the question that patients actually care about: not "will I get cancer from this?" but "will this scan more likely increase or decrease my lifespan and/or quality of life?".

I went to the doctor complaining of constipation. He sent me for a CT scan which showed that I was literally full of shit. The prescription was for a large dose of MiraLax. Now I wonder if the risk of the CT scan was really justified given that plenty of people already tell me that for free and without radiation.

Things like this are why we don't run general screening for rare diseases.

The risk from screening, and the risks from further diagnosis and accidental treating of false positives can be much higher than the disease itself as long as it is rare enough.

Scott Alexander’s article on altruistic kidney donation weighed the initial CT scan as a heavy negative, like an incremental 1 in 650 risk of death. Shocking to me at the time, but the number seemed to check out, at least as a first order estimate.

I’ve gotten heart scans twice to monitor coronary artery calcification and get an Agatson score. I wonder how risky this is? I feel like the last time I did it the technician said that the amount of energy they have to use now is much less due to advances in CT scanning machines.

I guess a heart scan is about like six months of natural background radiation according to this chart.

https://www.radiologyinfo.org/en/info/safety-xray

My father’s side has a history of heart attacks, so I’m trying to avoid that fate and consider the risks worth it.