Spinning the Statistics - Moving Targets

When you calculate a percentage the denominator is a critical variable.  If you want a small percentage just inflate the denominator toward infinity.  Consequently when you want the vaccine to be 99.99% effective just increase your timeline, enlarge your population comparison base and restrict your numerator to as small a number as possible.   Let me give you and example of playing with the timeframe:

The definition of  "fully vaccinated"  is 14 days from the second shot.  Vaccinations didn't start until 12/14/2020 with only 541individuals with the second shot.  The USA surpassed a million people with the second shot on 1/11/2021 - 1,317,291.   But that number is not lagged by the 14 day rule.  On 1/11/2021 only 8,515 individuals would have had their second shot for 14 days. 

So let's say one of the two shot vaccinated individuals contracted COVID and died on 1/11/2021.  The 14 day rule eliminated 1,308,776 in process vaccinated individuals from consideration in the percentage calculation. It is highly probable that this two shot vaccinated individuals would be considered "unvaccinated".  

Now if you start counting anything (cases, hospitalizations, deaths) as of 12/14/2020 it should be evident you denominator is very large by 1/11/2021 and yet the "fully vaccinated" population is only 8,515 available to contract COVID, get hospitalized, and if unlucky tragically die.   Also remember the death rate lags any positive test by as much as 3 weeks or more. 

So lets say one of the 8,515 individuals tested positive for COVID-19 on 1/11/2021.  If that person died three weeks later it would be 2/1/2021.  Have you "stopped" the denominator from growing from the unvaccinated and the partially vaccinated for proper comparison during that three weeks?

So let's use a real live example - New York City.  

 

Do you see the problem?   The denominator is as big as possible and the numerator (by definition) is as small as possible.  

I can make the vaccine "work" at nearly 100% efficacy by just changing my definition of "fully vaccinated" from14 days to 60 days (note the vaccine has only been administered for about 218 days).   

What is the lesson here.   When you have no control group you are dealing with moving targets.

Addendum 10:49am  -  Another variables to consider.  (1) % of population with antibodies (i.e. symptomatic and asymptomatic survivors).  (2) % of population unavailable to be vaccinated