Baseline data on community infections
We developed a sequential assessment of the risk reduction provided by face coverings using a step-by-step approach. As a baseline, we utilised the Office of National Statistics (ONS) Population Survey data to determine the baseline total number of community-derived infections.13The ONS Population Survey released on the 24th July 202013 provided data that estimated, for the most recent week for which data was available (13 to 19 July 2020). This excluded those in hospitals, care homes or other institutional settings (but not those who work in these settings). This baseline figure of 2,800 cases per day is used in subsequent modelling.