Survival Analysis of Hospital Length of Stay of COVID-19 Patients in Ilam Province, Iran: A Retrospective Cross-Sectional Study

Round 1

Reviewer 1 Report

1.     The capital letter in the title should follow the journal guideline 

2.     The headings in abstract should be deleted

3.     COVID-19 in Abstract should be defined first 

4.     L38-40: Need references

5.     L78: Polymerase Chain Reaction (PCR) --Should be polymerase chain reaction (PCR) 

6.     L130-132: need a reference no

7.     References section need to be revised following the journal guideline

8.  The labels of x and y should be clear with the unit – Define LOS. 

Need some edit related to the English 

Author Response

Dear Respectable Reviewers

Thank you for your valuable comments. Undoubtedly, your valuable comments helped us to improve the quality of our manuscript. We have answered all the comments in a clear manner and in cases where it was not possible to change, we have added the necessary explanations. I hope the honorable reviewers are satisfied with our answers. I apologize for the delay in sending the corrections due to some personal problems.

Cheers

Reviewer-1

1. The capital letter in the title should follow the journal's guideline 

Thank you. We edited our title based on recently published articles and journal guidelines. Our changes are highlighted with track changes.

2. The headings in the abstract should be deleted

Thank you for your comment but our abstract follows journal style. There are headings in the abstract of all published articles. But the headings are not bold.

3. COVID-19 in the Abstract should be defined first 

Added as requested.

4. L38-40: Need references

Added as requested.

5. L78: Polymerase Chain Reaction (PCR) --Should be polymerase chain reaction (PCR) 

Revised as requested.

6. L130-132: need a reference no

Added as requested.

7. The References section needs to be revised following the journal guideline

Revised as requested.

8. The labels of x and y should be clear with the unit – Define LOS. 

The definition of the length of stay was added to the introduction when we stated LOS for the first time. The unit is days of survival. We added days in the results section. 

Need some edits related to the English 

Revised as requested.

Reviewer 2 Report

I read the manuscript by Momeni et al. on the association between survival and length of stay of COVID-19 patients. The paper is original and interesting. However, I have some issues to be addressed:

- Line 45. COVID-19 does not only affect the lungs. In fact, several studies have been investigating COVID-19 related cardiovascular manifestations (doi: 10.1038/s41371-020-0387-4 - doi: 10.1111/echo.15462), renal (doi: 10.1111/aor.14078), hematological (doi: 10.1111/ijlh.13412) and cutaneous (doi: 10.1111/dth.13549). Please discuss and add these 5 references.

- Line 93. Survival and death are the same outcome, please report only one.

- Line 92-100. Please include it in a sub-paragraph called "statistical analysis".

- Line 110. Please specify that the days you are referring to are the days of hospital stay.

- Figure 1. Please specify the abbreviations used in the figure.

- Line 137. Please replace "corona patients" with COVID-19 patients.

Author Response

Dear Respectable Reviewers

Thank you for your valuable comments. Undoubtedly, your valuable comments helped us to improve the quality of our manuscript. We have answered all the comments in a clear manner and in cases where it was not possible to change, we have added the necessary explanations. I hope the honorable reviewers are satisfied with our answers. I apologize for the delay in sending the corrections due to some personal problems.

Cheers

Reviewer-2

I read the manuscript by Momeni et al. on the association between survival and length of stay of COVID-19 patients. The paper is original and interesting. However, I have some issues to be addressed:

- Line 45. COVID-19 does not only affect the lungs. Several studies have been investigating COVID-19-related cardiovascular manifestations (doi: 10.1038/s41371-020-0387-4 - doi: 10.1111/echo.15462), renal (doi: 10.1111/aor.14078), hematological (doi: 10.1111/ijlh.13412) and cutaneous (doi: 10.1111/dth.13549). Please discuss and add these 5 references.

Thank you for your comments. We revised the text as requested and added the related references.

- Line 93. Survival and death are the same outcome, please report only one.

Revised as requested.

- Line 92-100. Please include it in a sub-paragraph called "statistical analysis".

Revised as requested.

- Line 110. Please specify that the days you are referring to are the days of hospital stay.

Revised as requested.

- Figure 1. Please specify the abbreviations used in the figure.

Added as requested.

- Line 137. Please replace "corona patients" with COVID-19 patients.

Revised as requested.

Reviewer 3 Report

In this paper, the authors analyzed the survival of hospitalized patients with COVID-19 and the influence of certain factors on the outcome.

- The title of the paper is not the clearest and needs to be corrected.

- No abbreviation for COVID 19 was introduced in the summary.

- It is recommended that the authors use the term length of hospitalization instead of length of stay.

- In the methodology, the authors suggest that it is a cross-sectional study, while in the limitations they state that they retrospectively analyzed the data, it is necessary to clearly point out what type of study it is.

- Exclusion criteria are missing in the methodology.

- In the results, pay attention to the too large difference in the length of hospitalization between individual patients with a range of variation of 1-32 days. Did the authors take into account the effect of the applied therapy on the outcome. Data on laboratory parameters are missing. 

- Perform a regression analysis of the impact of therapy (antibiotics, immunosuppressants...) and laboratory parameters on the outcome.

- In the discussion, avoid repeating the results, analyze the data already obtained more precisely in relation to the studies published so far.

In this paper, the authors analyzed the survival of hospitalized patients with COVID-19 and the influence of certain factors on the outcome.

- The title of the paper is not the clearest and needs to be corrected.

- No abbreviation for COVID 19 was introduced in the summary.

- It is recommended that the authors use the term length of hospitalization instead of length of stay.

- In the methodology, the authors suggest that it is a cross-sectional study, while in the limitations they state that they retrospectively analyzed the data, it is necessary to clearly point out what type of study it is.

- Exclusion criteria are missing in the methodology.

- In the results, pay attention to the too large difference in the length of hospitalization between individual patients with a range of variation of 1-32 days. Did the authors take into account the effect of the applied therapy on the outcome. Data on laboratory parameters are missing. 

- Perform a regression analysis of the impact of therapy (antibiotics, immunosuppressants...) and laboratory parameters on the outcome.

- In the discussion, avoid repeating the results, analyze the data already obtained more precisely in relation to the studies published so far.

Author Response

Dear Respectable Reviewers

Thank you for your valuable comments. Undoubtedly, your valuable comments helped us to improve the quality of our manuscript. We have answered all the comments in a clear manner and in cases where it was not possible to change, we have added the necessary explanations. I hope the honorable reviewers are satisfied with our answers. I apologize for the delay in sending the corrections due to some personal problems.

Cheers

Reviewer-3

In this paper, the authors analyzed the survival of hospitalized patients with COVID-19 and the influence of certain factors on the outcome.

- The title of the paper is not the clearest and needs to be corrected.

Revised as requested. There are several published manuscripts such as our paper and we revised our manuscript based on this published article. If there is another amendment that the honorable reviewer wants, we will gladly do it.

- No abbreviation for COVID-19 was introduced in the summary.

Added as requested.

- It is recommended that the authors use the term length of hospitalization instead of length of stay.

Thank you for your comment. We mean Hospital length of stay and edit it through the text based on your recommendation. Also, we add a clear definition for it in the introduction section.

- In the methodology, the authors suggest that it is a cross-sectional study, while in the limitations they state that they retrospectively analyzed the data, it is necessary to clearly point out what type of study it is.

Thank you for your comments. We revised it based on your comments. Our study I a retrospective cross-sectional study.

- Exclusion criteria are missing in the methodology.

Added as requested. “The cases that had incomplete data or the desired data were not recorded for them were excluded from the study.”

- In the results, pay attention to the too large difference in the length of hospitalization between individual patients with a range of variation of 1-32 days. Did the authors take into account the effect of the applied therapy on the outcome? Data on laboratory parameters are missing. 

Thank you for your very good comment. Unfortunately, due to the lack of access to relevant data, this issue has not been investigated. This point was added to the study limitations section.

- Perform a regression analysis of the impact of therapy (antibiotics, immunosuppressants...) and laboratory parameters on the outcome.

Thank you for your comments.  We have not access to the data and we cannot perform such analyses.

- In the discussion, avoid repeating the results, and analyze the data already obtained more precisely in relation to the studies published so far.

Thank you. Revised as requested.

Author Response File: Author Response.docx

Round 2

Reviewer 3 Report

the authors did not fully respond to the reviewer.

it is necessary to process the underlying data in terms of regression analysis

the original version of the paper has been improved, but the results still need to be improved

Author Response

Dear Respectable Reviewers

Thank you for your valuable comments. Undoubtedly, your valuable comments helped us to improve the quality of our manuscript. We have answered all the comments in a clear manner and in cases where it was not possible to change, we have added the necessary explanations. I hope the honorable reviewers are satisfied with our answers. I apologize for the delay in sending the corrections due to some personal problems.

Reviewer-3

The authors did not fully respond to the reviewer.

It is necessary to process the underlying data in terms of regression analysis

The original version of the paper has been improved, but the results still need to be improved

Thank you again for your feedback. We respond to your comments and add regression analysis for underlying data. I hope these results satisfy you with this manuscript. Please look at Table 2 for regression analysis (highlighted in red).

Cheers

Round 3

Reviewer 3 Report

The authors answered all the reviewers' questions. I think that a satisfactory quality of work has been achieved.