"Cochrane ignored this epidemiological evidence because it didn't meet its rigid standard. I have called this approach “methodological fetishism,” when scientists fixate on a preferred methodology and dismiss studies that don't follow it. Sadly, it's not unique to Cochrane. By dogmatically insisting on a particular definition of rigor, scientists in the past have landed on wrong answers more than once."

https://www.scientificamerican.com/article/what-went-wrong-with-a-highly-publicized-covid-mask-analysis/