When working today about COVID-19 mortality, I was falling back to the survivorship bias that is nice illustrated at Wikipedia and which is just another type of selection bias that I explained in my last talk.
During World War II, the statistician Abraham Wald took survivorship bias into his calculations when considering how to minimize bomber losses to enemy fire.The Statistical Research Group (SRG) at Columbia University, which Wald was a part of, examined the damage done to aircraft that had returned from missions and recommended adding armor to the areas that showed the least damage, based on his reasoning. This contradicted the US military’s conclusions that the most-hit areas of the plane needed additional armor.
So far in epidemiology case – control studies are defined by an approach where
… the past histories of patients (the cases) suffering from the condition of interest are compared to the past histories of persons (the controls) who do not have the condition of interest, but who otherwise resemble the cases in such particulars as age and sex ….