Concerns With and Recommendations for Coronavirus Disease 2019 Research Related to Asymptomatic Infection and Mask Wearing

To the Editor—We read with interest the recent study by Sims et al [1]. The authors of this serological study of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among 20 614 healthcare workers (HCWs) in Michigan concluded that employees who wore an N95 filtering facepiece respirator or a powered air-purifying respirator had a significantly higher asymptomatic SARS-CoV-2 infection (ASI) proportion relative to those who wore a surgical mask or “other mask.” Here, we highlight some pressing concerns with this article.