You’re dealing with populations here. Literally the odds of a positive being false would be over 90%. Much higher in the more rare conditions. I’m not exaggerating. That means every almost every follow up you do is a waste of time, money and limited resources, denying care to those who need it. Including you when you actually do need it. It also exposes you to the risks of unnecessary follow-ups like infection. Your expected outcome is worse this way.
replyThe chance a positive is real is so low you may as well just point to a body part and get it biopsied.
A positive from this kind of test is statistically meaningless.
It's scary in both directions.
replyIf you let it give out tons of false positives, then patients are trained to ignore it when it cries wolf.
If you dial it back so that it gives out fewer positives, then now it starts giving out false negatives and not helping sick people.
Heh, Signal Detection Theory strikes again! This problem is as old as detecting whether a radar blip is a WW2 bomber on its way or not.
replySadly, there's no perfect threshold when the signal and noise distributions overlap substantially, just different trade-offs.
(Love CI, btw!)
You're right. I wrote a bad response at midnight. I meant to say something more narrow and specific: genomic assessments and new biomarker tests will become affordable and add information.
replyFor example, single nucleotide polymorphisms. This way doctors spend less time guessing which medication is likely to work best for you when there are many options available.
That doesn't sound like a useful test then. Instead use tests with fewer false positives.
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