PONE-D-22-17377Interleukin6 prediction of mortality in critically ill COVID19 patients: a prospective observational cohort studyPLOS ONE

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PLOS ONE

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6.  We noticed you have some minor occurrence of overlapping text with the following previous publication(s), which needs to be addressed:

- https://pubmed.ncbi.nlm.nih.gov/32845568/

- https://link.springer.com/article/10.1007/s12011-020-02437-9?code=1df3a266-3ae1-4a34-8d0a-a94b5b77b46a&error=cookies_not_supported

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Additional Editor Comments:

I found this manuscript interesting.In introduction, the rationale and gap need to be more precisely addressed.

The discussion should bring out the implications and novelty of the study in a more robust way.

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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

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

Reviewer #1: Yes

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

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Reviewer #1: Yes

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

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Reviewer #1: Yes

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5. Review Comments to the Author

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Reviewer #1: In this manuscript, investigators examined clinical and laboratory parameters associated with COVID19 mortality among patients admitted to the ICU in Tunisia. They found that IL-6 measured within 24 hours to the ICU predicted subsequent ICU mortality. IL-6 correlated with other biomarkers including CRP, D-dimer and zinc. Invasive mechanical ventilation also predicted subsequent ICU mortality. In general, there are some minor issues but the study is technically sound. The results are not novel because similar findings have been reported in multiple other investigations.

1) Please specify the method used to determine the cutoff from the ROCs. It may be ideal to pick a value with higher sensitivity.

2) Please specify that the associations with IL-6 and other biomarkers is statistically significant but fairly weak. This possibly accounts for the lack of association among the other biomarkers and ICU mortality.

3) It is not specified whether the patients were mechanically ventilated within 24 hours or at any point during the hospitalization.

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Reviewer #1: Yes: Manish Sagar

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Interleukin6 prediction of mortality in critically ill COVID19 patients: a prospective observational cohort study

PONE-D-22-17377R1

Dear Dr. JAMOUSSI,

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

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

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Kind regards,

Jacopo Sabbatinelli, MD, PhD

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

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2. 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

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

Reviewer #1: I Don't Know

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4. 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

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5. 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

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6. 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: Authors have addressed previous comments

I would have a statistics expert review the ROC analysis. In general there are strict criteria selected for selecting the cutoff.

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7. 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: Manish Sagar

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