PONE-D-24-02124Risk Factors Affecting Spinal Fusion: A Meta-Analysis of 39 Cohort StudiesPLOS ONE

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PLOS ONE

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-https://link.springer.com/article/10.1007/s10143-023-02041-0?

https://journals.lww.com/international-journal-of-surgery/fulltext/2023/10000/risk_factors_of_epidural_hematoma_in_patients.30.aspx

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“This work was supported by the Health and Family Planning Commission Program of Hunan Province (no. 202204074707), the Health and Family Planning Commission Program of Wuhan City (no. WX18C29), and Natural Science Foundation of Hunan Province (no. 2022JJ30516).”

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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: Partly

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

Reviewer #1: Yes

Reviewer #2: I Don't Know

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Reviewer #1: Yes

Reviewer #2: No

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Reviewer #1: Yes

Reviewer #2: Yes

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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: Thank you for submitting your work to PLOS ONE. The study aims to explore the potential risk factors regarding nonunion after spinal fusion surgery, leveraging a comprehensive meta-analysis approach.

Before considering this manuscript for publication, I recommend a major revision based on the following aspects.

1. Surgical variability and fusion rate analysis should be added. Your study predominantly focused on general risk factors affecting spinal fusion without considering the influence of surgical variability, such as the type of surgery or the site of surgery. Given that these variables can significantly impact fusion outcomes, it would enhance the manuscript's value to report on how different types of surgeries or fusion sites correlate with fusion rates. It offer a more nuanced understanding of risk factors.

2. Inclusion of forest plots in the main manuscript, not in supplement materials. While it is noted that forest plots were provided as supplementary figures, integrating these plots into the main figures of the manuscript would likely improve the accessibility and interpretability of your results for readers.

3. I also recommend adding tables that show baseline characteristics of the references, such as country, type and site of surgery, sample size, mean follow-up period, as well as included variables and significant variables for each reference.

Reviewer #2: 1. In statistics and other analyses

1) There is a need to explain the data extraction process in meta-analysis in more detail.

2) The method for calculating the effect size of data extracted from each study must be described. Then, the authors must explain in detail how authors integrated these effect sizes and performed statistical analysis.

2.From the results,

1) The authors mentioned MIS and the number of fused levels, and it seems that this should be described as a factor to be analyzed in the method. All factors to be analyzed must be introduced in the method, and the analysis details must be reported in the results.

2) The authors found that factors that inhibit spinal fusion, such as smoking, diabetes, vitamin D deficiency, graft type, pedicle screw type, and fusion column, were extracted from 39 studies, but the number of studies was small, with only more than 500 subjects or an I2 value of more than 0.5. Is this why it is classified as high or medium quality? I think we need to present objective standards for this.

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Reviewer #1: No

Reviewer #2: No

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Risk Factors Affecting Spinal Fusion: A Meta-Analysis of 39 Cohort Studies

PONE-D-24-02124R1

Dear Dr. Mingjiang Luo

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,

Jae-Young Hong

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Authors well revised the manuscript. 

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

Reviewer #2: (No Response)

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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

Reviewer #2: Yes

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

Reviewer #1: Yes

Reviewer #2: Yes

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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

Reviewer #2: 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

Reviewer #2: 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: Thank you for your vigorous effort to improve the manuscript according to the reviewers' comments. This manuscript seems much improved and met the reviewers's expectations.

Reviewer #2: Reviewer’s comments pointed out in the first review have been revised to comply. However, there are too many duplicate tables, and need to be organized. So, I recommend making a few changes to this.

1) First, I think it would be a good idea to organize and merge Table 1 and S2 table into one.

2) Also, the S1 table is explained in the Search strategy, but it would be better to supplement the content here and eliminate the table.

3) The S4 Table is also shown in Figure 1, so there is no need to insert it.

4) I think it would be a good idea to organize Table 2 and S6 Table and combine them into one.

Also, Figures S2 to S10 do not specify what the explanation is.

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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: No

Reviewer #2: No

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