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In their article, Bundgaard and colleagues report the results of a unique randomized controlled trial of masks in the community to mitigate SARS-CoV-2 infection. The trial addresses the question of personal protection to mask wearers when others are not wearing masks and not the question of the effectiveness of widespread mask wearing in reducing community transmission. The editorialists discuss the findings and their concerns about the trial design.
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Frieden et al. (2020) studied this question.
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