But I think if there is any criticism you can apply to some of the stuff he talks about it is that there is no hierarchy of evidence.

NEWYORKER: The Operator

In the accepted hierarchy of evidence generation, the results of a randomized, controlled clinical trial usually take precedence over other forms of evidence such as meta-analysis and observational studies.

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To understand the hierarchy of medical evidence, you need a bit of insight into how doctors perform these three types of studies and the terminology they use to describe results.

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