SteveAWOL
Distinguished Member
Looks like even when the UK finally achieves 100,000 tests per day we’ll still have thousands of people being incorrectly diagnosed, as whatever the NHS eventually end up using will provide similar accuracy to the antibody tests recently approved by the FDA over in USA.
This Cellex test has a "sensitivity" of 93.8% so of those who have actually been infected 6.2% will receive a false-negative result and end up self isolating unnecessarily.
Whilst the "specificity" of 95.6% means a false-positive rate of 4.4% and these individuals could be considered eligible for the “immunity passports“ despite never having been infected with SARS-CoV-2.
So if the proportion of general population who are infected is actually 1% then Bayes Theorem shows that 82% of positive results will in fact be false, meaning thousands of people every day potentially being lead to believe they’re immune when they’ve yet to be infected
This Cellex test has a "sensitivity" of 93.8% so of those who have actually been infected 6.2% will receive a false-negative result and end up self isolating unnecessarily.
Whilst the "specificity" of 95.6% means a false-positive rate of 4.4% and these individuals could be considered eligible for the “immunity passports“ despite never having been infected with SARS-CoV-2.
So if the proportion of general population who are infected is actually 1% then Bayes Theorem shows that 82% of positive results will in fact be false, meaning thousands of people every day potentially being lead to believe they’re immune when they’ve yet to be infected
Thread by @taaltree: Antibody tests are coming online. Never before have humans needed to understand Bayes rule more. Let's talk about why it's critical NOT to a…
Thread by @taaltree: Antibody tests are coming online. Never before have humans needed to understand Bayes rule more. Let's talk about why itical NOT to assume you are immune to covid-19 when you have a positive antibody test. Seriously, people need to u…
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