Originally Posted by
jfsully
This paper doesn't say what the article claims. The idea that "participants" had more infections than "nonparticipants" seems to be the crux of the claim, and the author assumes that the participant group was doing social distancing, masks, etc., while the nonpartipants served as a control. This is not the case, which is why the nonparticipants are referred to as "nonparticipants" and not "controls".
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So this study does NOT compare masks vs no-masks, and does not prove anything other than that the safety measures in place did not entirely prevent spread of infection. This is not surprising. The fact that only 2% of this group got infected suggest that some if not all of the safety measures were effective, but can't sort out how much effect each measure had. IE, maybe hand-washing and 6ft distance maximize protection, or maybe they are unneeded if you are wearing a mask. By looking at populations where precautions are low, I would have expected a spread of way more than 2% if the safety measures were ineffective.