4) Germany has more extensive testing than other European countries.
True, but South Korea had 3 times more tests per capita and 3 times more mortality (1.2%) than Germany. (Is Germany testing predominantly young people?)
5) The mortality in the other countries is way too high because they are not testing enough.
True, but that doesn't explain Germany's astonishingly low mortality.
6) Germany is not doing post-mortem testing in pneumonia cases.
Is this true? Several people mentioned it but I can't confirm. Any references?
7) A combination of several of the above
The point is not that European countries, including Germany, should be able to correctly estimate #COVID19 mortality at this time.
In fact, estimating unbiased case fatality risks (CFRs) isn't possible at this stage of the epidemic, as we explain here: journals.plos.org/plosntds/artic…
The point is that the EU needs a coordinated exit strategy for #COVID19 if it wants to preserve a union without borders and a sense of common purpose.
Making sure that data are collected in a consistent way would be a good first step towards a European solution.
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1/ One day everyone will recognize #selectionbias due to a #collider and the world will be a better place.
This time observational studies found a higher risk of omicron reinfection after a 3rd dose of #COVID19 vaccine. As usual, alarms went off.
Can you see the obvious bias?
2/ Those who receive a booster and get infected are, on average, more susceptible to infection than those who don't receive a booster and get infected.
So no surprise than those who receive a booster and get infected are more likely to get reinfected.
1/ Our findings on a fourth dose (2nd booster) of the Pfizer-BioNTech #COVID19 vaccine are now published.
Compared with 3 doses only, a fourth dose had 68% effectiveness against COVID-19 hospitalization during the Omicron era in persons over 60 years of age.
@ProfMattFox 1/
The odds ratio from a case-control study is an unbiased estimator of the
a. odds ratio in the underlying cohort when we sample controls among non-cases
b. rate ratio in the underlying cohort when we use with incidence density sampling
No rare outcome assumption required.
@ProfMattFox 2/
Because the odds ratio is approximately equal to the risk ratio when the outcome is rare, the odds ratio from a case-control study approximates the risk ratio in the underlying cohort when we sample controls among non-cases and the outcome is rare.
But...
@ProfMattFox 3/
... for an unbiased estimator of the risk ratio (regardless of the outcome being rare), we need a case-base design, not a classical case-control design.
Of course, all of the above only applies to time-fixed treatments or exposures.