Healthy. wrote:
If DTaP effectiveness is initially 95%, so that the risk of pertussis in vaccinated children is only 5% that of unvaccinated children,
These "effectiveness" numbers are literally stupid. They ASSUME that every vaxxed kid who DOESN'T get the disease would have contracted it otherwise (somehow).
But the obvious subgroup of vax-free students in this case has NONE of them being infected. So what are they comparing to in this "risk" assessment?
0/18 = 0% (exact)
30/1582 = 1.9% [their bogus method, reality is likely 30/200 or something, even if "highly contagious"]
The quotient risk is thus *infinitely* higher for their "effective" vaccine, as exposed by their own mathematics!
No it isn't stupid, it's statistics, and no they don't assume anything like that. You don't seem to know what you're talking about.
Yes, in this case, there are no infected non-vaccinated members of the sample, so there's no way to calculate the relative odds. Now we have to ask if the selected sample is of any use, or is representative of the population, or is big enough to be statistically significant (not likely, but it's 3 numbers lifted from a news article anyway).
Every single one of the studies cited in this thread -- every one -- either suggests or states explicitly the significant effectiveness of vaccination, yet whoever is posting them has completely mistaken them as evidence of the opposite. The papers, when you actually read them, all show evidence in favor of vaccination.
Has it occurred to you that the people writing them know some things that you don't?
Vaccines work.