PONE-D-20-10057

Time-to-Death approach in revealing Chronicity and Severity of COVID-19 across the World

PLOS ONE

Dear Dr Verma,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

This paper is very relevance in the context of ongoing pandemic. The reviewers have suggested some corrections. Their comments are appended below. In particular, the objective section is too long. Some of them are rational and can be merged with the introduction. Objective section should be brief and clear. Similarly, the method section can be replaced with Data and Method, which should have two sub-section of Data and Method. As reviewer suggested, clearly specify the assumptions of the method.

We would appreciate receiving your revised manuscript by Jun 08 2020 11:59PM. When you are ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter.

To enhance the reproducibility of your results, we recommend that if applicable you deposit your laboratory protocols in protocols.io, where a protocol can be assigned its own identifier (DOI) such that it can be cited independently in the future. For instructions see: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols

Please include the following items when submitting your revised manuscript:

• A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). This letter should be uploaded as separate file and labeled 'Response to Reviewers'.
• A marked-up copy of your manuscript that highlights changes made to the original version. This file should be uploaded as separate file and labeled 'Revised Manuscript with Track Changes'.
• An unmarked version of your revised paper without tracked changes. This file should be uploaded as separate file and labeled 'Manuscript'.

Please note while forming your response, if your article is accepted, you may have the opportunity to make the peer review history publicly available. The record will include editor decision letters (with reviews) and your responses to reviewer comments. If eligible, we will contact you to opt in or out.

We look forward to receiving your revised manuscript.

Kind regards,

Kannan Navaneetham

Academic Editor

PLOS ONE

Journal requirements:

When submitting your revision, we need you to address these additional requirements:

1.    Please ensure that your manuscript meets PLOS ONE's style requirements, including those for file naming. The PLOS ONE style templates can be found at http://www.plosone.org/attachments/PLOSOne_formatting_sample_main_body.pdf and http://www.plosone.org/attachments/PLOSOne_formatting_sample_title_authors_affiliations.pdf

2. We suggest you thoroughly copyedit your manuscript for language usage, spelling, and grammar. If you do not know anyone who can help you do this, you may wish to consider employing a professional scientific editing service.  

Whilst you may use any professional scientific editing service of your choice, PLOS has partnered with both American Journal Experts (AJE) and Editage to provide discounted services to PLOS authors. Both organizations have experience helping authors meet PLOS guidelines and can provide language editing, translation, manuscript formatting, and figure formatting to ensure your manuscript meets our submission guidelines. To take advantage of our partnership with AJE, visit the AJE website (http://learn.aje.com/plos/) for a 15% discount off AJE services. To take advantage of our partnership with Editage, visit the Editage website (www.editage.com) and enter referral code PLOSEDIT for a 15% discount off Editage services.  If the PLOS editorial team finds any language issues in text that either AJE or Editage has edited, the service provider will re-edit the text for free.

Upon resubmission, please provide the following:

●      The name of the colleague or the details of the professional service that edited your manuscript

●      A copy of your manuscript showing your changes by either highlighting them or using track changes (uploaded as a *supporting information* file)

●      A clean copy of the edited manuscript (uploaded as the new *manuscript* file)

 

[Note: HTML markup is below. Please do not edit.]

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

**********

2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: I Don't Know

**********

3. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

**********

4. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

**********

5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: The research topic is very relevant contemporary. The findings of the research will make a good contribution to understand the situation of current pandemic. The title of the research is concise and indicates the content of the research. The abstract is well structured and presents the relevant information. The background provides a good contextual information about the research with a proper logical flow and clear expression and very good use of professional language. Method section is very well described and all the stages of data analysis are clearly explained. Statistical analyses are performed accurately. The findings of the research will have a huge impact for future research development. Ethical issues are considered and concluding remarks are inline with the research findings.

Reviewer #2: A very well written paper that proposed a modelling to predict the duration of exposure to COVID-19 and its impact on mortality in several countries and then across the globe. This idea can be adopted by other affected countries in the world and also for any other future outbreak. This sort of finding is very useful to health service authorities in planning urgent strategies to be implemented on a timely manner to tackle the burden of the outbreak. The model was developed and then validated on a hold out data, which shows that model's prediction performance is very good.

However, I have a few queries to authors:

(a) what are the underlying assumption/s of this modelling technique; please address them (if any) clearly in the method section of the paper;

(b) across the globe the number of COVID-19 cases are dropping due to social distancing and other measures. My concern is whether the model can be useful to capture this downfall of confirmed cases.

Reviewer #3: Reviewer’s comments

Objective: It should be specific.

• The author mixed justification of the study and possible recommendation of the study under objective, e.g. first 12 sentences under the headline (Objective) belong to justification. And part of last sentence e.g. “Which will help in planning strategies required to be implemented in time”. It appears as a recommendation based on study findings.

Methodology:

• Based on mortality rate the author sets the affected countries into three category. As per categories, the predicted mortality rates were grouped into 3 groups. Group 1: 1 to 5%, Group 2: 6 to 10% and group 3: 20 to 50%. It is not clear to me what about 11 to 19% is.

• Methodology means what the author does to conduct the study. Therefore, first two sentences in page 6 may be reformulated.

Result:

• 7th line Page 6, it will be 28th.

• Group 3: 20 to 50%. Percentage of 11 to 19 is missing.

• 11th line “For category I country, the prediction was ……………………………………………………………. having mortality rates of 20-50%.” It is same as methodology. Sentences needs to be modified if it is result.

I am not a statistician. Therefore, a statistician must critically analysis statistical part e.g.:

• Statistical formula

• Figure on inverse probability analysis for total deaths

• Pattern of probability death occurrence

Discussion:

• Discussion part may be shorten by omitting duplication of sentences used in result section.

• There is no reference in discussion. If similar study on prediction of lethal duration is conducted on other communicable diseases that may be used as reference for discussion.

Conclusions:

• Contents of conclusions should include only finding of the study. In one sentence future term is used that needs to be corrected.

• First sentence and third sentences of conclusions may be deleted.

• Part of last sentences e.g. “Would eventually help to implement strategies to tackle this pandemic by taking necessary appropriate steps.” Better to mention what are the necessary steps; if the author identified some of the necessary steps.

**********

6. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: Yes: Russell Kabir

Reviewer #2: Yes: Baki Billah

Reviewer #3: No

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files to be viewed.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email us at figures@plos.org. Please note that Supporting Information files do not need this step.

Time-to-Death approach in revealing Chronicity and Severity of COVID-19 across the World

PONE-D-20-10057R1

Dear Dr. Verma,

We are pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it complies with all outstanding technical requirements.

Within one week, you will receive an e-mail containing information on the amendments required prior to publication. When all required modifications have been addressed, you will receive a formal acceptance letter and your manuscript will proceed to our production department and be scheduled for publication.

Shortly after the formal acceptance letter is sent, an invoice for payment will follow. To ensure an efficient production and billing process, please log into Editorial Manager at https://www.editorialmanager.com/pone/, click the "Update My Information" link at the top of the page, and update your user information. If you have any billing related questions, please contact our Author Billing department directly at authorbilling@plos.org.

If your institution or institutions have a press office, please notify them about your upcoming paper to enable them to help maximize its impact. If they will be preparing press materials for this manuscript, you must inform our press team as soon as possible and no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org.

With kind regards,

Kannan Navaneetham

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments: