1. COVID-19: unvaccinated face 11 times risk of death from delta variant, CDC data show;Dyer;BMJ,2021
2. AJMC staff. A Timeline of COVID-19 Vaccine Developments in 2021 2021. Available from: https://www.ajmc.com/view/a-timeline-of-covid-19-vaccine-developments-in-2021 (accessed December 20, 2021).
3. CDC. COVID Data Tracker 2021. Available from: https://covid.cdc.gov/covid-data-tracker/#datatracker-home (accessed December 20, 2021).
4. Lukpat A. The U.S. is falling to the lowest vaccination rates of the world’s wealthiest democracies. N Y Times 2021.
5. Using behavioral insights to increase vaccination policy effectiveness;Betsch;Policy Insights Behav Brain Sci,2015