PONE-D-20-17573

Comparisons of fatigue between dialysis modalities: A cross-sectional study

PLOS ONE

Dear Dr. Maruyama,

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 and will need major revisions in order to be considered for publication. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

In particular, the aims of this study should be clarified (validation study versus assessment of fatigue accross different dialysis modality), the use of POMS instead of SF-36 needs further justification and more emphasis should be given to the difficulties (and limitations) of interpreting results when using different measures of fatigue as presented in this study. The discussion should focus more on the outcome of fatigue then interventions to improve fatigue. 

Please submit your revised manuscript by Sep 06 2020 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're 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.

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). You should upload this letter as a separate file labeled 'Response to Reviewers'.
• A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.
• An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

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

We look forward to receiving your revised manuscript.

Kind regards,

Andrea K. Viecelli

Academic Editor

PLOS ONE

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2.Thank you for stating the following financial disclosure:

 [This study was supported in part by research grants from Baxter International, Inc. (number 16CECPDAP0002). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.].              

Please provide an amended statement that declares *all* the funding or sources of support (whether external or internal to your organization) received during this study, as detailed online in our guide for authors at http://journals.plos.org/plosone/s/submit-now.  Please also include the statement “There was no additional external funding received for this study.” in your updated Funding Statement.

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[I have read the journal's policy and the authors of this manuscript have the following competing interests: Y.M. and M.N. have received scholarship funds from Baxter International, Inc. and Terumo Corporation. No other authors have any conflicts of interest to declare.].

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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

Reviewer #2: Partly

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

Reviewer #1: Yes

Reviewer #2: Yes

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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: No

Reviewer #2: Yes

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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: No

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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: I read with interest the manuscript “Comparisons of fatigue between dialysis modalities: A cross-sectional study” by Maruyama and colleagues. This study provides interesting findings on fatigue in different dialysis modalities, as assessed through three different fatigue evaluation scales (POMS, VAS and an original scale).

Nevertheless, I have a few comments and questions to ask the authors. For simplicity, I will comment by sections.

METHODS

Subjects

1. Could the authors comment on how the patients were screened for inclusion in the study? Were all patients in the included centers screened for inclusion? Was there a minimum duration of dialysis for inclusion (eg. established on dialysis for at least 3 months)?

2. The authors specify that “any patient that had a diagnosable mental health disorder or medical illness, including dementia and terminal cancer were excluded”. As patients with depression, CVD, diabetes, etc. are included in this study, it appears that the “diagnosable mental health disorder or medical illness” warranting exclusion from the study were more specific. The authors should further specify the exact exclusions and/or modify this statement in the manuscript.

Assessments of fatigue and depression

3. All used scales are very well described in the manuscript. However, no details are provided on how the responses to the self-reported questionnaires/scales were collected: were the patients completing the questionnaires in a written form by themselves or verbally answering to the questions to a member of staff? The authors should provide more details on the exact “self-reporting” procedure and if any exclusion from the study would have been related to these. For example, if the questionnaires were completed in a written format, were patients unable to write/read excluded or offered any help to complete the questionnaire?

Statistical analysis

4. Were the variables included in the multivariate analysis chosen on biological/clinical plausibility alone or was a univariate analysis done? As smoking was significantly different across groups, can the authors explain why it was not included in the multivariate analysis?

RESULTS

5. Following on question #1, the authors should provide some information on the included cohort compared to the dialysis population in the participating centers. How many patients were screened for inclusion; how many were excluded and for which reason, etc? This might also need to be mentioned in the limitations of the study depending on the representativity of this cohort compared to the dialysis population screened.

6. Can the authors comment on the predominantly male cohort: is this proportion representative of the dialysis population in Japan or is this related to higher consent to study by men or exclusion of more women due to exclusion criteria?

7. Could the authors provide a brief statement on modality choice in the participating centers (HD vs HDF vs PD vs combined HD/PD): patients’ choice, medical indication, ‘PD first’ policy, etc?

8. In the introduction, the authors mention that “It is unclear whether dialysis-related factors such as the type of dialysis modality and the adequacy or frequency of dialysis are associated with fatigue”. Were data on dialysis prescription (number of exchanges and volume of PD; treatment time and frequency on HD, etc) and on dialysis adequacy (Kt/v or URR) collected as part of this study? If so, these should be described and potentially included in the regression models. If these data were not collected, it should be mentioned in the limitation of the study as they could potentially be important confounders.

9. In the paragraph describing results included in Tables 2 and 3 (p.10-11), the same sentences appear twice. Table 2 describes the logistic regression model for highest score of fatigue (dichotomic outcome) and not the severity of fatigue. This should be corrected in the manuscript. In the second part of that paragraph (describing Table 3), the same sentence describing the association of employment status is used, mentioning the “lower risk of fatigue”. Here, it appears that this results should refer to a “lower severity/score of fatigue” (continuous outcome).

DISCUSSION

10. Could the authors comment on the median VAS and POMS values obtained in their study compared to previous studies?

For example, in a Malaysian study comparing quality of life in HD vs CAPD, mean VAS scores were around 76-77 vs. 48 in the present study.

[Surendra NK, Abdul Manaf MR, Hooi LS, et al. Health related quality of life of dialysis patients in Malaysia: Haemodialysis versus continuous ambulatory peritoneal dialysis. BMC Nephrol. 2019;20(1):151. Published 2019 Apr 30. doi:10.1186/s12882-019-1326-x]

In contrast, a Polish study evaluating defense mechanism in dialysis patients found the fatigue subscale of the POMS around 5-11 vs. 11.3 in the present study.

[Nowak Z, Wańkowicz Z, Laudanski K. Denial Defense Mechanism in Dialyzed Patients. Med Sci Monit. 2015;21:1798-1805. Published 2015 Jun 22. doi:10.12659/MSM.893331]

The generalizability of the results from the present study should be mentioned in the discussion in light of such differences or similarities.

FIGURE 1

11. In Figure 1, for the graph representing the results from the original scale, asterixis (*) are used but no legend for this is provided.

In conclusion, this manuscript presents very interesting findings on severity of fatigue in different dialysis modality, including the combined therapy of PD and HD, which is used much more frequently in Japan than elsewhere in the world. The cross-sectional, observational nature of the study, the potential for selection bias and residual confounding are limitations of this study, which have been clearly identified by the authors in the discussion.

Please note that the data underlying the findings is described as fully available within the manuscript and its Supporting Information files on the submission but no supporting files were attached to the manuscript for review so I cannot comment on the “full availability” of the data.

Reviewer #2: While fatigue is very important for patients on dialysis, I'm not sure that this study adds anything new to the existing body of literature on this topic. Furthermore, I have outlined some major methodological concerns below.

Aim - It is unclear whether the aim is to investigate the levels of fatigue across dialysis modalities or validate a new fatigue measure the authors have created

Introduction:

- Second last paragraph: QOL and fatigue are not interchangeable so this paragraph seems a bit random – either explain how fatigue impacts QOL and thus is the research question for this study, or explore literature around fatigue instead

- Last paragraph: why would comparing modalities expected to help identify which subjects will benefit from interventions to reduce fatigue?

Methods:

- I think the authors should justify why POMS was chosen for this study. If frequency of use was the basis, why wasn’t SF-36 used? POMS includes a subscale for fatigue but given that it is more of a symptom checklist-type measure with a focus on ‘moods’ than a symptom-specific questionnaire, it seems an odd choice of measure to which the authors’ measure is compared

- What was the sampling methodology?

- The readers would benefit from greater details about the ‘original measure’. How was it developed/through what process? Has the content validity been established? Is this the first time that it has been used in a study? Why/how were grades 3, 4 and 5 chosen as ‘fatigued states’? Is this measure described else where in the literature? If so, please add in the relevant citation

- Depression needs to be better integrated into the rationale of this study

Results:

- Given that POMS, VAS and the original scale were all used to explore fatigue, the rho seems quite low. explore this in the discussion

- POMS and VAS did not differ across four groups, but the original scale did – what does this tell us about the fatigue levels across these groups? Or what does this say about the validity of the original scale?

Discussion

- Discrepancy in results in existing literature regarding fatigue may also be due to the fact that measures of fatigue vary across these studies (as evident in this study where different measures yield different results)

- Discussion on the interventions for fatigue seems out of place – link the results of this study back to what the implications are for future research aiming to look at interventions for fatigue across different modalities

- 4th limitation is noted as the fact that ‘convergent and discriminant validity, test-retest reliability or social desirability could not be clarified using this study design’. This is a major flaw of this study, as using a measure that has not been adequately validated runs the risk of yielding not only inconclusive but also misleading results. I would advise that the authors rethink the true aim of this study

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Reviewer #1: No

Reviewer #2: 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.]

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 PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

PONE-D-20-17573R1

Comparisons of fatigue between dialysis modalities: A cross-sectional study

PLOS ONE

Dear Dr. Maruyama,

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.

The authors have addressed previous comments. However, the manuscript needs significant editing to comply with standard English. There are too many typographical or grammatical errors to list here. The manuscript is not publishable in the current state and will require major editing and revisions. The original data set referred to under “supporting information” was not available to the editor or reviewer and will need to be accessible in order to comply with publication criteria. In addition to the reviewer’s comment, there are additional issues identified that require clarification:

Abstract:

Please avoid vague statements in the abstract like “The scores of the POMS, VAS, and our original scale of fatigue were weakly but significantly inter-related”. The actual results would be more helpful.  

“In the fatigue scales of on dialysis day by 3 tests, there were no statistical differences by modalities.” The meaning of this sentence is unclear. Please clarify and revise.

“The similar result was obtained in 122 patients without depression.” “The” should be removed.

The conclusion of the abstract and manuscript is unclear and needs rephrasing. What do the authors mean with “The results indicated the least impact of dialysis modalities on fatigue in dialysis patients including HD, online HDF, PD and combined therapy with PD and HD.”?

Methods: “All participants read and wrote questionnaires for themselves”. Participants presumably did not write the questionnaires but responded to the questions without assistance.

The references need reformatting.

Please submit your revised manuscript by Dec 06 2020 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're 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.

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). You should upload this letter as a separate file labeled 'Response to Reviewers'.
• A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.
• An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

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

We look forward to receiving your revised manuscript.

Kind regards,

Andrea K. Viecelli

Academic Editor

PLOS ONE

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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: (No Response)

**********

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

**********

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

Reviewer #1: Yes

**********

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

**********

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: No

**********

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: I read with interest this new version of the manuscript “Comparisons of fatigue between dialysis modalities: A cross-sectional study” by Maruyama and colleagues.

The questions and concerns raised in the first review process have been answered and addressed. However, I have a few additional comments about this new version.

1) The main aim of this study was to evaluate fatigue across different dialysis modalities. When adjusted for patient characteristics, no association was found between occurrence and severity of fatigue and dialysis modality. The authors should review the conclusions section in the abstract and the main article as the current wording is hard to understand and does not clearly describe the findings.

2) In the second paragraph of the Introduction, the authors refer to “patients on” HD and PD and the different hypotheses for the mechanisms of fatigue of each modality. The causes described seem to refer to the modality themselves, and not the patients.

3) At the end of the Introduction section, the aim is described as the comparison of prevalence OR severity. This should be modified to “and” as the authors evaluated both the prevalence and the severity with 2 different regression models.

4) The last sentence of the introduction is misleading as the authors state that the findings could “indicate the different pathophysiology of fatigue by dialysis modalities”. Although the findings might raise new questions and hypotheses on the pathophysiology of fatigue across modalities (with the differences seen between on and off dialysis days in HD and HDF), this study is not designed to evaluate the pathophysiology of fatigue.

5) The authors indicate that their original fatigue scale has been previously used in other studies, but they do not indicate if it has been validated as an accurate scale. The authors could specify in the Methods section why they have also used their original scale (easy to use? readily available?) if the aim of the study was not to validate this new scale.

6) The authors have indicated in this new version of the manuscript that their original scale was used on both on- and off-dialysis days in HD and HDF, with differences in the scores obtained. However, the authors do not mention if the scale was also used on different days in the combination therapy (HD+PD) group. Since the study aimed to compare the modalities and seemed to raise differences in fatigue depending on the timing of dialysis session, it would have been relevant to test whether fatigue also varied depending on timing in the combination therapy group, in which patients are treated alternatively with PD and HD. As timing of assessment of fatigue is not mentioned in this group, it brings some doubts about the reliability of the findings in this group if the timing related to HD sessions was not the same for all patients (for example: a patient assessed on HD day vs. a patient assessed after 3 PD days and due for HD 3 days later). If timing of assessment was different across the groups, this should be mentioned in the discussion.

In conclusion, this study reports interesting findings on fatigue in dialysis. The use of the original scale is interesting, but needs validation. The aim of the study was to compare fatigue across modalities. The findings related to the original scale are therefore hard to interpret as this scale has not been formally validated/compared to other scales.

The differences seen between on- and off-dialysis days also raise hypotheses on differences in the pathophysiology of fatigue across dialysis modalities. The inclusion of patients on combination therapy in this study is interesting (as this modality is mostly used in Japan). However, the methodology described did not permit to fully evaluate the differences across modalities without major confounding (including the timing of assessment in that group). Perhaps this would warrant further research in this group of patients who alternate between HD and PD.

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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.

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Reviewer #1: 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.]

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 PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

PONE-D-20-17573R2

Comparisons of fatigue between dialysis modalities: A cross-sectional study

PLOS ONE

Dear Dr. Maruyama,

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.

==============================

The suggested minor revisions are included in the edited tracked version attached and relate predominantly to the conclusion of the abstract and the manuscript. Further minor edits and grammatical corrections have been made throughout the manuscripts.

==============================

Please submit your revised manuscript by Feb 27 2021 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're 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.

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). You should upload this letter as a separate file labeled 'Response to Reviewers'.
• A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.
• An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

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

We look forward to receiving your revised manuscript.

Kind regards,

Andrea K. Viecelli

Academic Editor

PLOS ONE

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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

**********

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

**********

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

Reviewer #1: Yes

**********

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

**********

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

**********

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: (No Response)

**********

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

[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.]

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 PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

Attachments

Attachment

Submitted filename: Revised Manuscript with Track Changes PONE 20201201_Revised.docx

PONE-D-20-17573R3

Comparisons of fatigue between dialysis modalities: A cross-sectional study

PLOS ONE

Dear Dr. Maruyama,

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.

Suggested revisions have been attached (Edited revision 3) to ensure the conclusions are supported by the data (please note the current version implies a causal relationship rather than an association). Comments have been added in the manuscript version attached to outline further minor revisions including the limitation of the small sample size and improvement of the first paragraph in the discussion to reflect a concise summary of the findings. Without these amendments, the manuscript does not fulfil the publication standards. The editor encourages the authors to address the suggested edits and revisions.

Please submit your revised manuscript by Mar 07 2021 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're 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.

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). You should upload this letter as a separate file labeled 'Response to Reviewers'.
• A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.
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Attachments

Attachment

Submitted filename: Revised Manuscript with Track Changes PONE 20201201_RevisedV2.docx

Comparisons of fatigue between dialysis modalities: A cross-sectional study

PONE-D-20-17573R4

Dear Dr. Maruyama,

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.

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Kind regards,

Andrea K. Viecelli

Academic Editor

PLOS ONE

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