Pfizer reported that its vaccine shows a 95% efficacy. That sounds like it protects you 95% of the time, right? But that’s not actually what that number means. That 95% refers to the Relative Risk Reduction (RRR), but it doesn’t tell you how much your overall risk is reduced by vaccination. For that, we need Absolute Risk Reduction (ARR).
During the Pfizer trial, 0.88% of the placebo group got covid-19 and 0.04% of the vaccinated group got covid-19. So the ARR or net benefit that you’re being offered with the Pfizer vaccine is 0.84%. That 95% number refers to the relative difference between 0.88% and 0.04%. That’s what they call 95% RRR.
Relative Risk Reduction is well known to be a misleading number, which is why the FDA recommends using Absolute Risk Reduction instead, which begs the question of how many people would have chosen to take the COVID-19 vaccines had they understood that they offered less than 1% benefit❓
https://kanekoa.substack.com/p/the-powerful-pfizer-presentation