Do medical staffs need to wear masks? - Arguments based on best evidence

Objective whether the medical staff need to wear masks or not is still controversial, the aim of this study is to evaluate and summarize the best evidence relevant to this topic in order to provide sugges-tions for the medical staff.Methods PubMed, Cochrane Library, web of science, CINAHL, CNKI, Wan-fang, VIP, CBM, guideline databases and related professional societies were systematically searched from the inception of the database to 27 October 2019 in order to relevant guidelines, expert consensus and systematic reviews. The researchers assessed the quality of best evidence included using international recognized quality evaluation tools, and summarized the recommendations on whether the medical staff need to wear masks or not.Results 35 documents were included, including 6 guidelines, 27 expert consensus, 2 systematic reviews, and the overall quality of the evidence was higher. According to the ev-idence, masks were recommended as one of the personal protective measures, and wearing masks has obvious advantages in the prevention of nosocomial infection compared with the nonuse of respiratory protective equipment. The evidence also put forward a number of recommendations based on different clinical scenarios workplace such as operation area, laboratory area, obstetrics.Conclusion Wearing masks is well recognized by the existing best evidence to prevent nosocomial infection. However, the quality of the evidence still has certain limitations. The medical staff should use masks reasonably consid-ering their experience, clinical settings, or other factors.