Earlier quoted context omitted.
I think a lot of this comes down to replication, effect size, and sample size. Yes, there are studies which show virtually everything, but in this case, we have: - >10% of mild cases reporting long COVID brain fog (without MRIs) - Visible correlations on MRIs with large n (cited study) - Lots of small-scale studies / looking at specific cases - Some understanding of a relevant mechanism-of-action (see: olfactory loss…
> >10% of mild cases reporting long COVID brain fog (without MRIs) "Brain fog" is not a diagnosis. It has no definition. It has no test. Literally anyone could say they have it, and not be wrong. It also overlaps substantially with "fatigue"...which we all know comes along with a lot of other common issues. Such as depression. > Visible correlations on MRIs with large n (cited study) The size of n doesn't matter if t…
Can you please propose a "randomized, longitudinal, controlled trials" one might conduct to figure that out?
Preferably, one which would pass an IRB review. We can't randomly infect 10,000 ethnic minorities with COVID19 anymore, which I think what you're suggesting. The Tuskegee Syphilis Study and the Nuremberg Trials took care of that for us.
Short of something like that, we work from mixed methods evidence.
As a footnote, a year isn't a long time in the world of research. That's sometimes quite literally how long it takes from when you apply for a grant to when funding lands in your account. And you're asking about a phenomenon which often occurs months later.