Preprint / Version 1

Analyzing the Accuracy of Reporting of SARS-CoV-2 Infections Across Six Countries


  • Hyunjin Lim Polygence



COVID-19, SARS-CoV-2, Accuracy, Reporting


The outbreak of the COVID-19 pandemic prompted a global response that involved hundreds of government bodies and international organizations. As part of this response, large amounts of data on infection rates, hospitalizations, and fatalities was reported. Verifying the accuracy, reliability, and consistency of reported data is important for establishing public trust and scientific consensus. Here, I search for inconsistencies in  COVID-19 case reporting and analyze their various causes, including variations in testing capabilities, healthcare infrastructure, governmental policies, and data collection methodologies. I analyzed reported COVID-19 case data from South Korea, the United States, the United Kingdom, France, China, and Japan. For each nation, I compared time-course data on the number of positive cases, the number of deaths, and the per-case mortality rates to identify discrepancies. I found that almost all nations showed consistent trends in case rates, indicating global waves of infections. I also found a consistent decrease in the per-case mortality rate, possibly caused by access to better prophylactics and medicines along with SARs-CoV-2 evolving to be less virulent. However, we found massive anomalies in China's state reported data when compared with other nations. I think this is likely due to government censorship of infection data. I hope that the work I present here will help to increase confidence in reported data and will provide tools and strategies for international organizations to build trust in data collected from collaborating nations during a global pandemic. 


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