Oh yeah, I'd forgotten about that. I just assumed more research had been done since to connect them.
Discussion
Studies that find nothing don't get published.
100 fair studies will have 5 that show a positive result where none exists because of the statistical threshold for publishing.
Publish or perish means that researchers are motivated to find a result.
This leads to a lot of bunk getting published in peer reviewed journals. The Reproducibility Crisis is a major problem that gets almost no mainstream press. We may be better than pre scientific method but we are far from perfect in our methods.
Makes sense when it comes to the less hard sciences.
I recall the autism one being particularly bad, to the point of obvious deception, but haven't looked into it in a long time.