The vaccine efficacy illusion revisited

Note error: At 0:54 I said “10% vaccinated by week 14“ when I should have said “10% unvaccinated by week 14“ (as is correctly shown in the table). Why classifying a person as unvaccinated for the first 2 or 3 weeks after vaccination is guaranteed to result in high efficacy results for a vaccine that is just a placebo (or worse). This s a realistic simulation that reproduces the same kind of efficacy results as were claimed in the UK vaccine roll out. For further details see: 6 May 2023 Update: Quite a few people have asked why we are including those vaccinated within the last 21 days in the ‘total vaccinated’ denominator for the vaccinated infection rate if such people are classified as unvaccinated. The answer is that, while those infected within 21 days are classified as unvaccined in observational trials, those who are not infected are generally treated as vaccinated. In observational studies, which is what we are simulating here, there is no pre-defined vaccine and control group as there would be in a controlled trial. And, unlike a controlled trial, people are getting vaccinated at different times. Hence, everything is driven by looking at ‘cases’ i.e. those defined to have been infected in any given week; all those infected within 21 days of a vaccination are classified as unvaccinated. However, for the efficacy calculation at any time, for the ‘denominators’ they simply use the total number of people vaccinated so far (e.g. from NIMS) and for this, there is generally no ‘21 day delay’.
Back to Top