New Paper (Other): Epidemiological parameters of coronavirus disease 2019: a pooled analysis of publicly reported individual data of 1155 cases from seven countries

[dziakj1]

Title: Please edit the title to add the name of the paper after the colon.

General Information

Please paste a link to the paper or a citation here:

Link: https://www.medrxiv.org/content/10.1101/2020.03.21.20040329v1.full.pdf

What is the paper's Manubot-style citation?

Citation: @doi:10.1101/2020.03.21.2004032

Is this paper primarily relevant to Background or Pathogenesis?

• [ ] Background
• [ ] Pathogenesis
• [ ] Methods

Please list some keywords (3-10) that help identify the relevance of this paper to COVID-19

• basic reproduction number
• incubation period
• latent period
• serial interval

Please note the publication / review status

• [x] Pre-print
• [ ] New Peer-Reviewed Paper
• [ ] Peer-Reviewed Paper Pre-2020

Which areas of expertise are particularly relevant to the paper?

• [ ] virology
• [x] epidemiology
• [ ] biostatistics
• [ ] immunology
• [ ] pharmacology
• [ ] other:

[dziakj1]

Summary

Suggested questions to answer about each paper:

• What did they analyze? The authors studied "10728 publicly available reports released by the health authorities of and outside China and from 1790 publications identified in PubMed and CNKI," apparently finding them by Internet search and reviewing them by hand. These were all "laboratory confirmed cases of COVID-19." The authors extracted as much information as they could from each.

• What methods did they use? They tried to get maximum likelihood estimates of important epidemiological parameters,

• Does this paper study COVID-19, SARS-CoV-2, or a related disease and/or virus? It is specifically about COVID-19.

• What is the main finding (or a few main takeaways)? "The mean and standard deviation were 7.44 days and 4.39 days for incubation period, 2.52 days and 3.95 days for the upper limit of latent period, 6.70 days and 5.20 days for serial interval, and -0.19 day (i.e., 0.19 day before infector’s symptom onset) and 3.32 days for time point of exposure. R0 was estimated to be 1.70 and 1.78 based on two different formulas. For 39 (6.64%) cases, the incubation periods were longer than 14 days. In 102 (43.78%) infector-infectee pairs, transmission occurred before infectors’ symptom onsets. In 27 (3.92%) infector-infectee pairs, infectees’ symptom onsets occurred before those of infectors."

• What does this paper tell us about the background and/or diagnostics/therapeutics for COVID-19 / SARS-CoV-2? I am not an expert in this area but I do not feel confident in the methods they used or in their grasp of statistical theory.

• Do you have any concerns about methodology or the interpretation of these results beyond this analysis?

I have very serious concerns and am not sure whether this analysis can be interpreted usefully, because of the massively selected, nonrepresentative nature of the cases. I am sad about this because the study clearly involved a herculean amount of work for the authors to compile all these cases and review them, often one by one. One of the important parameters, the upper limit of the latent period, was estimated using only 11 patients out of the total 1155, being the only ones for whom the required information was available, which is surely missing not at random. I am not an epidemiologist but got the impression that the authors were massively devoted to their project but perhaps insufficiently skilled or resourced.

Any comments or notes?

I don't think it's necessary to cite this preprint.