Is the Observed Protection of COVID-19 Vaccines Against Infection within 14 days Real or an Artifact? A Negative Control Outcomes-Based Investigation Using Real-World Data

Authors: Bingyu Zhang, Qiong Wu, Ting Zhou, Dazheng Zhang, Jiayi Tong, Yuqing Lei, Martijn Schuemie, Patrick B. Ryan, Jeffrey S. Morris, George Hripcsak, Christopher B. Forrest, Yong Chen

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