That is, in actual fact, not the case. From an article at the beginning of the pandemic published by Oxford uni's Centre for Evidence Based Medicine (CEMB):
> Evidence from 14 trials on the use of masks vs. no masks was disappointing: it showed no effect in either healthcare workers or in community settings. We could also find no evidence of a difference between the N95 and other types of masks but the trials comparing the two had not been carried in aerosol-generating procedures.
It goes on, and helpfully points out the problems with these studies that means it would be hasty to use them as the final word.
> So we got into this situation unprepared with a faulty evidence base and hotly debated practices, after two decades of “pandemic preparedness”.
You'll note that the debate ended with the British Medical Journal's[2] executive editor, a proponent of masks who states that they think CEMB's review and subsequent articles on the subject are mistaken, defending the CEMB's views from being censored by Facebook:
> A disagreement among experts, especially about interpretation of a study, is a common occurrence. It is the usual business of science.
I wish I could make that bold and quoted.
> Only, Facebook didn’t see it that way. The social media platform that allows statements about injecting bleach to prevent covid-19, as well as calls to behead the leading US expert on pandemics,67 decreed that Heneghan and Jefferson should be censured for misinformation after they reposted their Spectator article on the site.
The Science™ certainly isn't settled on this, to portray as such does a disservice to the actual pursuit of truth. And that after lamenting bias in reporting.
> Perhaps we need to create a new degree program
You mean, like the CEMB has?[3]
> Our team research, practice and disseminate evidence-based medicine in health care decision making, and are committed to improving healthcare by fostering wider communication of high quality evidence, by promoting the principles of EBM through engagement, knowledge sharing, research and education.
[1] https://www.cebm.net/covid-19/covid-19-masks-on-or-off/