Systematic observation of mask adherence and distancing (SOMAD): Findings from Philadelphia

Adherence to guidelines for face coverings and physical distancing are critical strategies to stem the COVID-19 pandemic but are not uniformly followed. Understanding factors associated with adherence to mask-wearing and physical distancing may help guide future control efforts. We conducted an observational study using Systematic Observation of Mask Adherence and Distancing (SOMAD) in August 2020 in parks, playgrounds and commercial streets in each of 10 City Council Districts in Philadelphia, PA. Wearing a mask correctly varied by setting with highest adherence in commercial areas and lowest in playgrounds. Almost 17% wore visible masks that did not cover the nose and/or mouth. There were multiple disparities in correct mask use. Females had higher rates than males (unadjusted relative risk = 1.40, p < .0001) and seniors higher than any other age group (unadjusted chi-square p < .0001). Asians wore masks correctly the most often [adjusted log odds ratio (LOR) = 0.53 compared with non-Hispanic white, p = 0.02]. Correct mask-wearing was higher in areas with a higher population density (adjusted LOR = 0.03 per one thousand/square mile, p = 0.02) and lower in higher poverty areas (adjusted LOR = -0.01, p = .03). Disparities in adherence to mask wearing and physical distancing likely reflect differences in perception of risk by gender, age group, and race/ethnicity. While the risk of COVID-19 transmission is lower in outdoor settings, it is unlikely to be zero. The lower rates of mask use by males and minority groups suggest increased efforts are needed to enhance adherence to recommended guidelines.