My point was that testing people who wore a mask vs. those who didn’t and trying to draw conclusions based on their infection rate is the wrong thing to measure. They need to measure whether infected people who wore masks passed the virus to others. I don’t think there is any way to do that.
I think that is already covered in the Marine study. Contact limited with those outside the study as much as possible, strict mask protocols and rigorous testing as well as removal of positives as soon as they are detected, and still a 2% rate of infection. How else can that infection be spreading except despite the masks?