“Surgical masks reduce COVID-19 spread, large-scale study shows”

I’m placing this here for future reference a.k.a. the next time I need a pointer for someone who says that masks aren’t effective.

Stanford Medicine:

“A large, randomized trial led by researchers at Stanford Medicine and Yale University has found that wearing a surgical face mask over the mouth and nose is an effective way to reduce the occurrence of COVID-19 in community settings.”