I feel entitlement-vibes

I am cognisant of the editors warnings, but I want to make a factual correction:

> the evidence that they help prevent an infected person from spreading it is apparently quite strong.

This is incorrect. We have primary R(C)?CT evidence for protective effect on wearers, and enough of it for Cochrane to have been able to conduct their systematic reviews - though, the body of data there is still, by their standards, poor. We do NOT (TTBOMK) have any substantive evidence for this novel "source control" theory (i.e., that even if they do not protect wearer, they protect others) for masks. I.e., we don't even have any RCT.