Cohort study: Effectiveness of three vs. six feet of physical distancing for controlling spread of COVID-19 among primary and secondary students and staff

Effectiveness of three versus six feet of physical distancing for controlling spread of COVID-19 among primary and secondary students and staff: A retrospective, state-wide cohort study – Clinical Infectious Diseases

News release: With masks on, three feet is just as safe as six feet apart in Massachusetts schools, researchers find – Beth Israel Deaconess Medical Center