Positively Perplexed

Why are antibody tests inaccurate? The biostats, explained.

It seems complicated, but let's break it down.

Covid-19 antibody tests are tools scientists use to understand the epidemic.

But how useful they actually are right now, and if you should take one, is confusing.

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In some cases, a positive antibody test may only be right about half the time, reports the CDC.

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