How the case counting window affected vaccine efficacy calculations in randomized trials of COVID-19 vaccines.

Peter Doshi has received travel funds from the European Respiratory Society (2012) and Uppsala Monitoring Center (2018); grants from the FDA (through University of Maryland M-CERSI; 2020), Laura and John Arnold Foundation (2017–22), American Association of Colleges of Pharmacy (2015), Patient-Centered Outcomes Research Institute (2014–16), Cochrane Methods Innovations Fund (2016–18), and UK National Institute for Health Research (2011–14); was an unpaid IMEDS steering committee member at the Reagan-Udall Foundation for the FDA (2016–2020), and is an editor at The BMJ. Kaiser Fung declares no conflict of interest. Data sharing is not applicable to this article as no new data were created for this article.