This is something frequently missing from discussions like this.
Something that has a fairly small per-patient risk like a CT scan, causes far more pain than reduced missed diagnoses would solve if applied across the whole population.
asking as someone that had it
CT scans are super valuable for all sorts of things, and the radiation dose/risk for an individual is small, but at a societal level using them freely as a "might as well" kind of test results in a lot of excess radiation exposure. This recent research suggests up to 5% of cancer diagnoses each year could be from CT scan radiation: https://www.ucsf.edu/news/2025/04/429791/popular-ct-scans-co...
The "incidental findings" side is an interesting dilemma: CT scans often reveal other stuff beyond what they were initially ordered for, but which can't be identified solely by the CT scan itself. So, if something looks a little weird on the CT scan it creates an imperative to figure out what it is, so there are additional tests, each of which carries its own risks and also consumes limited resources that might otherwise have been used for people with more definitively concerning findings. https://en.wikipedia.org/wiki/Incidental_imaging_finding
A family member ran into this with a brain tumor, which for a patient presenting with a headache is a 1% likelihood. Slightly elevated blood pressure was the focus in that case. Persistence and a subtle symptom changed triggered the CT scan that ultimately led to the diagnosis about 8 weeks later. Unfortunately with melanoma, 8 weeks is a long time.
Ultimately there’s no right answer. 99% of people with headaches have high blood pressure or other “normal” causes. Sending 1,000 people to CT to identify 5 tumors will cause 50 other complications.
Think of doctors like a helpdesk in a big company. Open a ticket, but work your network to get someone who isn’t dumb to think about it. If you’re too poor or don’t have friends and advocates, your outcome will be no mas.