
‘How Could the CDC Make That Mistake?’ - jbegley
https://www.theatlantic.com/health/archive/2020/05/cdc-and-states-are-misreporting-covid-19-test-data-pennsylvania-georgia-texas/611935/
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timr
This is a misleading article. While it's true that an antibody test is capable
of detecting prior infections and a PCR test is not, this has little bearing
on the overall specificity/sensitivity profile of any particular test.

The main argument here appears to be that antibody tests have false negatives,
therefore antibody tests will make test numbers look artificially lower. But
there are antibody tests with very high specificity and sensitivity (relative
to PCR testing), and there are less-reliable PCR tests. Moreover, we _know_
there are error bars on these positive rates and case counts, and other
sources of error (e.g. sampling bias) likely play a much larger role in
uncertainty than false negatives in antibody tests.

If a clinic is using an IgG/IgM test (particularly one with a good
sensitivity/specificity profile), there's no reason not to include the results
with PCR data in aggregate stats. South Korea expanded testing primarily
through widespread antibody testing, so we're hardly alone here.

