Six-Month Effectiveness of BNT162B2 mRNA COVID-19 Vaccine in a Large US Integrated Health System: A Retrospective Cohort Study by Sara Y. Tartof, Jeff M. Slezak, Heidi Fischer, Vennis Hong, Bradley K. Ackerson, Omesh N. Ranasinghe, Timothy B. Frankland, Oluwaseye A. Ogun, Joann M. Zamparo, Sharon Gray, Srinivas R. Valluri, Kaijie Pan, Frederick J. Angulo, Luis Jodar, John M. McLaughlin :: SSRN

https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3909743