https://www.tabletmag.com/sections/science/articles/randomized-control-tests-doidge
The
idea that “only RCTs can decide,” is still the defining attitude,
though, of what I shall describe as the RCT fundamentalist. By
fundamentalist I here mean someone evincing an unwavering attachment to a
set of beliefs and a kind of literal mindedness that lacks nuance—and
that, in this case, sees the RCT as the sole source of objective truth
in medicine (as fundamentalists often see their own core belief). Like
many a fundamentalist, this often involves posing as a purveyor of the
authoritative position, but in fact their position may not be. As well,
the core belief is repeated, like a catechism, at times ad nauseum, and
contrasting beliefs are treated like heresies. What the RCT
fundamentalist is peddling is not a scientific attitude, but rather
forcing a tool, the RCT, which was designed for a particular kind of
problem to become the only tool we use. In this case, RCT is best
understood as standing not for Randomized Control Trials, but rather
“Rigidly Constrained Thinking” (a phrase coined by the statistician
David Streiner in the 1990s).
With such a good technique as RCTs, one might wonder, why do we ever bother with observational studies?
There
are a number of situations in medicine in which observational studies
are obviously superior to randomized control trials (RCTs), such as when
we want to identify the risk factors for an illness. If we
suspected that using crack cocaine was bad for the developing brains of
children, it would not be acceptable to do an RCT (which would take a
large group of kids, and randomly prescribe half of them crack cocaine
and the other half a placebo and then see which group did better on
tests of brain function). We would instead follow kids who had
previously taken crack, and those who never had, in an observational
study, and see which group did better. All studies ask questions, and
exist in a context, and the moral context is relevant to the choice of
the tool you use to answer the question. That is Hippocrates 101: Do no
harm.
Similarly, withholding the most promising treatment we have for a lethal illness is also a moral matter. That is precisely the position taken by the French researchers
who thought that hydroxychloroquine plus azithromycin was the most
promising treatment known for seriously ill COVID-19 patients, and who
argued that doing an RCT (which meant withholding the drug from half the
patients) was unconscionable. RCT fundamentalists called their study
“flawed” and “sloppy,” implying it had a weak methodology. The French
researchers responded, in effect saying, we are physicians first; these
people are coming to us to help them survive a lethal illness, not to be
research subjects. We can’t randomize them and say to half, sorry, this
isn’t your lucky day today, you are in the nontreatment group.
