How about this:
Almost 789,000 cased of Covid-19 have been identified in the U.S. Of those 73,533 have recovered fully and 42,458 have died. Of the 74,000 who recovered how many were given hydroxychloroquine as part of their treatment and how many were not? Of the 42,500 who died how many were given hydroxychloroquine and died anyway?
We can factor their prior conditions in in the study.
Perfect! Now you are getting it. The “Natural Course” of the disease can be known by the data we have. Sure, it is confounded minimally by the people who WERE treated by the proposed treatment and we can’t know that but with three quarters of a million people who have had the disease i think its pretty safe to say not enough of them are in the data set to terribly bias it.
So there you have it! A group of people who can inform us about what the course of the disease is.
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