On immunity passports, Bayesian statistics, and why a "95% accurate" test saying you& #39;ve had Covid-19 does not mean that there& #39;s a 95% chance you& #39;ve had Covid-19

(I think this is quite an important point that doesn& #39;t seem to have been addressed much?) https://unherd.com/2020/04/how-far-away-are-immunity-passports/">https://unherd.com/2020/04/h...

with thanks to @kjm2 for statistical sense-checks

I& #39;m going to tweet this one a few times because I worry that it& #39;s quite hard to make Bayesian statistics sound exciting, but it& #39;s genuinely easy to understand and really important. This question is key – and for the record, most doctors get it wrong: https://unherd.com/2020/04/how-far-away-are-immunity-passports/">https://unherd.com/2020/04/h...