Estimating the case fatality ratio of the COVID-19 epidemic in China
 View ORCID ProfileXing Wang,  View ORCID ProfileZihui Ma,  View ORCID ProfileYi Ning,  View ORCID ProfileChen Chen, Rujin Chen, Qiwen Chen,  View ORCID ProfileHeng Zhang,  View ORCID ProfileChunming Li,  View ORCID ProfileYan He, Tao Wang, Cheng Tong, Junqing Wu, Yuyan Li,  View ORCID ProfileHandong Ma,  View ORCID ProfileShaodian Zhang,  View ORCID ProfileHongxin Zhao 6park.com
doi: https://doi.org/10.1101/2020.02.17.20023630
This article is a preprint and has not been peer-reviewed [what does this mean?]. It reports new medical research that has yet to be evaluated and so should not be used to guide clinical practice. 6park.com
AbstractInfo/HistoryMetrics Preview PDF 6park.com

Abstract
Background: Corona Virus Disease 2019 (COVID-19) due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in Wuhan city and rapidly spread throughout China since late December 2019. Crude case fatality ratio (CFR) with dividing the number of known deaths by the number of confirmed cases does not represent the true CFR and might be off by orders of magnitude. We aim to provide a precise estimate of the CFR of COVID-19 using statistical models at the early stage of the epidemic. Methods: We extracted data from the daily released epidemic report published by the National Health Commission P. R. China from 20 Jan 2020, to 11 Feb 2020. Competing risk model were used to obtain the cumulative hazards for death, cure, and cure-death hazard ratio. Then the CFR estimation was calculated based on the slope of the last piece in joinpoint regression model, which reflected the most recent trend of the epidemic. Sensitivity analyses were performed by assuming an average period of observation stays for 3-7 days after recovery. Results: As of 11 Feb 2020, totally 44,653 cases were diagnosed as COVID-19 in mainland China. Assuming an average period of 5 days' observation stays after severe cases turned to be asymptotic, adjusted CFR of COVID-19 were 14.97% (95% CI: 14.22%-15.77%) in Hubei province, including Wuhan, the epicenter, and 0.52% (95% CI: 0.42%-0.71%) in other areas of China, respectively. We observed obvious decreasing trends of adjusted CFR for COVID-19, with two distinct turning points on January 26 and February 1 for Hubei province, and one turning point on January 28 for other areas, respectively. Conclusions: Based on analyses of public data, we found that the CFR in Hubei was much higher than that of other regions in China. The CFR would follow a downwards trend based on our estimation and recently released data. Nevertheless, at early stage of outbreak, CFR estimates should be viewed cautiously because of limited data source on true onset and recovery time. 6park.com
Competing Interest Statement
The authors have declared no competing interest