Supplementary Material for: Skin Barrier Damage due to Prolonged Mask Use among Healthcare Workers and the General Population during the COVID-19 Pandemic: A Prospective Cross-Sectional Survey in China

<b><i>Background:</i></b> Coronavirus disease 2019 (COVID-19) has resurged in localized areas in China. Individuals wear masks to prevent the spread of droplets. However, skin barrier damage occurs because of the prolonged use of masks. <b><i>Objective:</i></b> To investigate the prevalence and associated risk factors of skin injuries among healthcare workers (HCWs) and the general population during the COVID-19 outbreak. <b><i>Methods:</i></b> A multicenter cross-sectional study of skin barrier damage caused by wearing masks was conducted using an online questionnaire between December 10 and December 31, 2020. Data regarding demographics, characteristics of facial skin damage, and information on masks were registered. Multivariate logistic regression was used to analyze factors associated with skin barrier damage, and odds ratios (OR) with 95% confidence intervals (CI) were used to establish correlation strength. <b><i>Results:</i></b> A total of 1,538 responses were retrieved from 1,700 questionnaires (response rate, 90.47%), and 1,409 questionnaires were valid (effective response rate, 91.61%). The respondents comprised 567 HCWs (40.24%) and 842 individuals from the general population (59.76%). The prevalence of skin injuries was 46.03% among HCWs and 46.20% among the general population. History of chronic skin disease (OR, 6.01; 95% CI, 4.75–7.75), type of mask used (OR, 2.77; 95% CI, 1.95–3.93), daily wearing time (OR, 1.57; 95% CI, 1.36–1.82), and mask replacement cycle (OR, 0.76; 95% CI, 0.68–0.86) were associated with skin barrier damage. <b><i>Conclusion:</i></b> There was a high incidence of skin barrier damage due to prolonged mask use among HCWs and the general population, and treatment and prevention were inadequate. Attention needs to be given to strengthening comprehensive health education and popularization of science.

**背景**：2019冠状病毒病（COVID-19）在我国局部地区出现反弹。民众佩戴口罩以阻断飞沫传播，但长期佩戴口罩可引发皮肤屏障损伤。
**目的**：本研究旨在探讨新冠疫情期间，医护人员（healthcare workers, HCWs）与普通人群的皮肤损伤患病率及其相关危险因素。
**方法**：本研究于2020年12月10日至12月31日期间，通过线上问卷开展一项针对口罩佩戴所致皮肤屏障损伤的多中心横断面研究。研究收集了受试者人口学信息、面部皮肤损伤特征及口罩使用相关资料。采用多因素logistic回归分析皮肤屏障损伤的相关影响因素，并以比值比（odds ratios, OR）及95%置信区间（confidence intervals, CI）评估关联强度。
**结果**：本研究共发放1700份问卷，回收1538份，整体回收率为90.47%；其中有效问卷1409份，有效回收率为91.61%。受访者中包含567名医护人员（占比40.24%）与842名普通民众（占比59.76%）。医护人员与普通人群的皮肤损伤患病率分别为46.03%与46.20%。慢性皮肤病病史（OR=6.01，95%CI：4.75~7.75）、口罩类型（OR=2.77，95%CI：1.95~3.93）、每日佩戴时长（OR=1.57，95%CI：1.36~1.82）及口罩更换周期（OR=0.76，95%CI：0.68~0.86）均与皮肤屏障损伤存在显著关联。
**结论**：医护人员与普通人群因长期佩戴口罩导致的皮肤屏障损伤发生率较高，且当前防治措施存在不足。需重视加强综合健康教育与科学普及工作。