
EUA Authorized Serology Test Performance - wyndham
https://www.fda.gov/medical-devices/emergency-situations-medical-devices/eua-authorized-serology-test-performance
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Shank
For the uninitiated, the FDA faced criticism initially by being too slow to
authorize PCR tests for SARS-CoV-2 and issued a much more broad EUA for
serological tests. However, serological tests need to be run on known positive
and negative patients (already tested) to validate their accuracy. Because
infection with SARS-CoV-2 is relatively uncommon, and because the EUA is
broad, tests that offer the statistical value of a coin flip have been
authorized and used. This is a problem if you’re trying to make health
decisions.

So, the FDA is trying to advise people on this risk by providing tools to
judge the performance of serological tests to help clear up the confusion.
This is because many tests have rated performance based on a very small number
of people and the error bars are relatively large.

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makomk
Even the worst tests here provide a lot more information than a coin flip, as
I understand it. A 50% PPV at a prevalance of 5% means that if the odds of
someone having had coronavirus were 5% going into the test and they get a
positive result, you can immediately update your estimate of the odds of them
having had it to 50%, which isn't nothing.

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Animats
It looks like this technology is getting debugged. Some of the tests are well
above 99% for both specificity and sensitivity. Some aren't, and they will
probably be withdrawn from the market.

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FuckButtons
So from what I heard the other day, those >99% Numbers were from a subset of
the actual sample, which they argued was because of the requisite time lag for
seroconversion but may just be p-hacking.

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Animats
Cite?

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FuckButtons
Segment starts around 17 minutes:
[https://www.bbc.co.uk/sounds/play/m000jw02](https://www.bbc.co.uk/sounds/play/m000jw02)

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moose_ears
Related:
[https://open.fda.gov/apis/device/covid19serology/](https://open.fda.gov/apis/device/covid19serology/)

