You don't know how these studies are done. Almost always they are done by docs working in academia, who are usually on salary. They actually usually practice only part-time, and do research and teaching the bulk of their workloads. These docs make names for themselves by showing that what everyone else in their specialties are doing is wrong, and these academic docs can show them the "better way". They involve a statistician and an economist, who assign dollar values to various things, like "fear", and "false positive", and "stress".

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