Dr. Leffler discusses his team's analysis of the country-wide mortality from COVID-19 pandemic and its correlation with mask usage by the public.

Full reference:

Leffler CT, Ing E, McKeown CA, Pratt D, Grzybowski A. Final Country-wide Mortality from the Novel Coronavirus (COVID-19) Pandemic and Notes Regarding Mask Usage by the Public. April 4, 2020. Available from: researchgate.net.