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No. You are mathematically wrong. You need to start the efficacy on day 11 or so and compare to efficacy after day 21 (if wanting to compare to directly after dose 2) or day 31, etc. (if you wanted to compare efficacy 10 days after dose 2.)

Efficacy does not start on day 0 or 1 as you imply. Efficacy for those first 10 days or so appears to be zero, or close to it, for those first several days (10 or 11.) It takes time, so you need to subtract off the data that occurs before day 10 or 11 or whatever you choose. BUT, that needs to be clearly stated.

I'm unsure if you completely don't know what you are doing or are trying to mislead the audience. Either way, you are wrong.


James: Advise checking the data which is published.

Harry Johnson

Author is wrong.


HJ: I can't respond to that unless you tell us what you think is wrong.


If everyone was exposed to covid while getting their shot, efficacy would be zero using your flawed start at zero approach. None of the companies are reporting start at zero VE.


HJ: They are reporting it. The Pfizer chart would not start at Day 0 if it illustrated only cases starting at 7 days after 2nd dose. The Pfizer chart also does not lead to 95% efficacy unless you subtract the cases in the first 28 days. Every study since then have reported different case-counting windows, which usually includes Day 0.

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