TIL Researchers developed a blood test that can detect if a person has cancer from a single drop of blood with 96% certainty for most cancer types.

I'm not familiar with what "adjusted rate" is, could you explain?

I just want to add that is important to note that even if the true positive rate (sensitivity) were 100% and the false positive rate was 1% (specificity/true negative = 99%), it is still impossible to gauge how "great" this test is in practice because we have not defined the characteristics of the screening population.

Example I would give is that if I were to tell you that this test has sensitivity (true positive) of 100% and specificity (true negative) of 99%, then everybody (like people reading this headline) want to jump on board and get the cancer test. That is hugely problematic. Let's say that in the general population, for every person that has undetected cancer, 100 people do not. That means that for this impossibly great test with 100/99% sensitivity/specificity, if everybody gets it, then for every single true positive in the population you will have one false positive. People don't understand how a test like this could actually destroy people's lives. For every one person that you potentially save you are also sending another person down a road of serious distress with serious economic and social repercussions.

Just some perspective. Luckily the people in charge of determining whether such tests actually are recommended understand this fact, but this is more of a comment for all the millions of patients who will complain that this isn't covered by insurance or that their doctor won't do this or that test on them; it is because some tests can do more harm than good (which is why mammograms are also controversial and the appropriate screening population is a hotly debated subject).

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