Face masks ‘significantly reduce’ spread of Covid-19, study finds

While I could believe it, this study was essentially: 1) make assumptions about mask effectiveness 2) run a simulation model with a range of parameters of that effectiveness 3) conclude that masks significantly reduce spread

I'm not saying it's not worth doing, but it's substantially different than what the headline says. "Theoretically, masks should work to significantly reduce spread of Covid-19" would be more accurate.