Face masks for the...Face masks for the public during the covid-19 crisis;, , , , 1Nuffield Department of Primary Care Health Sciences, University of Oxford2Neonatal Department, University Hospital of Zurich, Switzerland3University of Zurich, Zurich, Switzerland4Institute for Advanced Studies, Vienna, Austria5London School of Economics, London, UK6University of Edinburgh, UK7University of Glasgow, UKCorrespondence to: T Greenhalgh Trisha Greenhalgh and colleagues argue that it is time to apply the precautionary principleThe precautionary principle is, according to Wikipedia, “a strategy for...…Face masks for the...Face masks for the public during the covid-19 crisis;, , , , 1Nuffield Department of Primary Care Health Sciences, University of Oxford2Neonatal Department, University Hospital of Zurich, Switzerland3University of Zurich, Zurich, Switzerland4Institute for Advanced Studies, Vienna, Austria5London School of Economics, London, UK6University of Edinburgh, UK7University of Glasgow, UKCorrespondence to: T Greenhalgh Trisha Greenhalgh and colleagues argue that it is time to apply the precautionary principleThe precautionary principle is, according to Wikipedia, “a strategy for...WW…