PONE-D-24-53720Prevalence of multimorbidity and its relationship with socioeconomic status among Chinese older adults over time: Evidence from CHARLS 2011-2018PLOS ONE

Dear Dr. Liu,

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.

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ACADEMIC EDITOR: Kindly pay attention to each comment from the reviewers and provide a rebuttal for each query.

REVIEWER 1

A well-written article. Some observations are noted as follows:

1. The use of only 14 chronic conditions could have limited the number of chronic diseases reported and hence underestimated the prevalence of multimorbidity.

2. The use of patient self-report can also be affected by recall bias, especially in the older adults who might have memory problems.

an objective assessment of chronic disease could have given the study more strength.

3. The use of diseases like kidney disease, digestive diseases, and psychiatric diseases might be nonspecific and can result in loss of important information.

REVIEWER 2

1. Title of the study

- The title of the study should be concise. The author is advised to avoid using acronyms in the title and remove the timeframe, as it can be addressed in the methodology section.

2. Abstract

- The first time ‘Socioeconomic Status’ appears in the abstract, it should be followed by its acronym in parentheses (SES).

3. Keywords

- Chronic conditions/diseases could be added as another key word.

4. Methods section

a. Data source and processing

- This sentence in the methods section requires revision for improved grammar and clarity, “To analyze the health problems of ageing in the social and economic transition period, this survey has collected sets of high-quality micro-data representing households and individuals of middle-aged and people aged 45 and above in China”.

- Could the authors clarify why they chose to isolate and analyze data only for individuals aged 60 years and above, despite the CHARLS study including older people starting from age 45? Additionally, it might be helpful to define who qualifies as an older adult in the context of this study.

b. Measures

- Multimorbidity – More detailed information is needed to explain why participants were limited to reporting only whether they had any of the 14 listed conditions.

- Socioeconomic status – This sentence needs to be referenced appropriately “Education, occupation and income are the three most commonly used indicators to measure socioeconomic status (SES)”.

5. Results

- Major results – I suggest the authors use ‘Results’ as the heading for this section. The current heading might imply the existence of ‘Minor Results,’ which could be misleading.

6. Discussion

- Main Findings: This subsection largely reiterates content already presented in the results section. It is recommended that this subsection be removed.

- Discussion: The discussion requires further strengthening. The authors primarily focus on the unidirectional relationship between SES and multimorbidity. For example, they should consider discussing instances where multimorbidity was higher among individuals with lower SES compared to the opposite. What possible factors might contribute to such findings, and how do these align with or differ from existing evidence?

- Recommendations: Beyond suggesting further studies, the authors should provide plausible recommendations for addressing the observed trends in multimorbidity in China.

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

Please submit your revised manuscript by Mar 15 2025 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.

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We look forward to receiving your revised manuscript.

Kind regards,

Godpower C. Michael, MBBS, MHE, FWACP

Academic Editor

PLOS ONE

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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: Yes

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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: Yes

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: 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: a well-written article. some observations are noted as

1. The use of only 14 chronic conditions could have limited the number of chronic diseases reported and hence underestimated the prevalence of multimorbidity.

2. The use of patient self-report can also be affected by recall bias, especially in the older adults who might have memory problems.

an objective assessment of chronic disease could have given the study more strength.

3. The use of diseases like kidney disease, digestive diseases, and psychiatric diseases might be nonspecific and can result in loss of important information.

Reviewer #2: 1. Title of the study

- The title of the study should be concise. The author is advised to avoid using acronyms in the title and remove the timeframe, as it can be addressed in the methodology section.

2. Abstract

- The first time ‘Socioeconomic Status’ appears in the abstract, it should be followed by its acronym in parentheses (SES).

3. Keywords

- Chronic conditions/diseases could be added as another key word.

4. Methods section

a. Data source and processing

- This sentence in the methods section requires revision for improved grammar and clarity, “To analyze the health problems of ageing in the social and economic transition period, this survey has collected sets of high-quality micro-data representing households and individuals of middle-aged and people aged 45 and above in China”.

- Could the authors clarify why they chose to isolate and analyze data only for individuals aged 60 years and above, despite the CHARLS study including older people starting from age 45? Additionally, it might be helpful to define who qualifies as an older adult in the context of this study.

b. Measures

- Multimorbidity – More detailed information is needed to explain why participants were limited to reporting only whether they had any of the 14 listed conditions.

- Socioeconomic status – This sentence needs to be referenced appropriately “Education, occupation and income are the three most commonly used indicators to measure socioeconomic status (SES)”.

5. Results

- Major results – I suggest the authors use ‘Results’ as the heading for this section. The current heading might imply the existence of ‘Minor Results,’ which could be misleading.

6. Discussion

- Main Findings: This subsection largely reiterates content already presented in the results section. It is recommended that this subsection be removed.

- Discussion: The discussion requires further strengthening. The authors primarily focus on the unidirectional relationship between SES and multimorbidity. For example, they should consider discussing instances where multimorbidity was higher among individuals with lower SES compared to the opposite. What possible factors might contribute to such findings, and how do these align with or differ from existing evidence?

- Recommendations: Beyond suggesting further studies, the authors should provide plausible recommendations for addressing the observed trends in multimorbidity in China.

**********

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:  Zainab Abdulazeez Umar

Reviewer #2: Yes:  Duncan Kwaitana

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Attachments

Attachment

Submitted filename: manuscript.docx

Prevalence of multimorbidity and its relationship with socioeconomic status among Chinese older adults over time

PONE-D-24-53720R1

Dear Dr. Liu,

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,

Godpower C. Michael, MBBS, MHE, FWACP

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments: nil

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: 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

Reviewer #2: Yes

**********

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

Reviewer #1: Yes

Reviewer #2: N/A

**********

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: No

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

**********

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: The author has noted the comments made and has been captured in the limitation section. The discussion needs some improvement, especially to address the relationship of multimorbidity and declined or reduced socioeconomic status.

Reviewer #2: Comments have been successfully addressed the comments and where necessary they have provided a rebuttal

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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:  Zainab Abdulazeez U.

Reviewer #2: Yes:  Duncan Kwaitana

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