PONE-D-24-02466COVID-19 vaccination intention among internally displaced persons in complex humanitarian emergency context, Northeast NigeriaPLOS ONE

Dear Dr. Gidado,

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 manuscript is well-written and timely, particularly given the invaluable insights garnered from navigating the challenges posed by the COVID-19 pandemic. It is imperative to document such experiences, especially concerning vulnerable populations, to inform future healthcare strategies effectively.

However, to provide a comprehensive understanding of the paper's context, it is essential to delineate the impact of the COVID-19 pandemic in Africa and Nigeria, particularly concerning morbidity, mortality, vaccination rates, and other pertinent information. This comparative analysis would elucidate the specific challenges faced by internally displaced persons (IDPs) and set the backdrop for the study's relevance.

While the paper employs various statistical methodologies, it lacks clarity regarding the percentage of IDPs, regardless of their formal or informal status, willing to accept the COVID-19 vaccine. Additionally, the issue of proximity to health facilities was highlighted, warranting further exploration, particularly in comparison to the general population. Also as COVID 19 is no longer a pandemic, can this also be reflected in the paper.

Further elaboration on the statistical methodologies employed would enhance the paper's accessibility, especially for readers with limited statistical proficiency. Clarification and additional information on these methodologies would mitigate confusion and facilitate a deeper understanding of the findings.

Lastly, it is advisable to limit references to publicly available "published work" and consider the feedback provided by Dr. Edina and Bassey. Their insights could further refine and strengthen the manuscript.

Please submit your revised manuscript by Apr 10 2024 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,

Sylvester Maleghemi Maleghemi, MD,MSC, DTH&M, MBA

Academic Editor

PLOS ONE

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3. Thank you for stating the following financial disclosure: 

"Saheed Gidado, the first and corresponding author, received funding from Tampere University, Finland. The funding covered the cost of transportation, accommodation, and allowances during the fieldwork of the study. The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript."

We note that one or more of the authors is affiliated with the funding organization, indicating the funder may have had some role in the design, data collection, analysis or preparation of your manuscript for publication; in other words, the funder played an indirect role through the participation of the co-authors. If the funding organization did not play a role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript and only provided financial support in the form of authors' salaries and/or research materials, please do the following:

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4. In the online submission form, you indicated that [Data cannot be shared publicly because the study was conducted in the context of armed conflict induced humanitarian emergency triggered by the insurgent activities of Non-State Armed Groups (NSAG) against the Nigerian Government. This setting is associated with enormous security concerns and risk, particularly for the internally displaced persons - the study population. However, the data are available from the corresponding author on request.]. 

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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: 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: Reviewer’s Comments

Thank you for the opportunity to review this manuscript which reports on the findings of a complex sample survey analysis conducted to determine the prevalence and factors associated with intention to accept COVID-19 vaccine among internally displaced persons (IDPs) living in Northwest Nigeria. Given the under-representation of IDPs in research studies with this focus and their general exclusion from COVID-19 mitigation programs at the height of the pandemic globally, the findings of this study should make an important contribution to informing equitable and responsive health care provision to this population. The manuscript is well written and presented. There are some aspects of the methodology and reporting which requires clarity.

Major Comments

To provide further context to the study, the authors should address – as part of the Background section - the burden of COVID-19 in Nigeria (e.g., cases, hospitalization and/or deaths) and provide clarity on the national COVID-19 vaccination program, including access and provision of COVID-19 vaccines among marginalized populations (e.g., IDPs) where possible.

With regards to the Methods, there is a need for further clarity on the types of data collected from the household surveys conducted in July – December 2023 and whether this survey is separate from the semi-structured interviews conducted in the current study. It is unclear from the methods whether the study design adopted was prospective or retrospective. In addition, it is unclear to me when the study activities were conducted (i.e., when were participants recruited and enrolled into this study? What was the duration of this study?).

While the comparisons made with findings from general populations from other countries are notable in the Discussion section, the authors are encouraged to also appraise their findings against similar studies conducted among migrant populations (whether IDPs or otherwise) in other parts of the world. For example, you would note from a recently published systematic review and meta-analysis that the findings on vaccine acceptance in this study are comparable, if not higher, than that reported previously among migrant populations globally [Hajissa K, Mutiat HA, Kaabi NA, et al. COVID-19 Vaccine Acceptance and Hesitancy among Migrants, Refugees, and Foreign Workers: A Systematic Review and Meta-Analysis. Vaccines (Basel). 2023;11(6):1070. Published 2023 Jun 6. doi:10.3390/vaccines11061070].

Minor Comments

• Line 38, page 2; “…were 18–39 years old, 82.6.0% were females…” Kindly confirm the proportion presented here.

• Line 88, page 5; “Furthermore, a recent, unpublished study conducted among IDPs…” Kindly note the journal guidelines on this and address appropriately: "Do not cite the following sources in the reference list: Unavailable and unpublished work, including manuscripts that have been submitted but not yet accepted (e.g., “unpublished work,” “data not shown”). Instead, include those data as supplementary material or deposit the data in a publicly available database."

• Line 126, page 6; “…and who had not received any dose of COVID-19 vaccine.” Kindly indicate how vaccination history was determined (participant recall or valid vaccination records?).

• Line 127 – 128, page 6; “Data of these participants were extracted from a complex sample, household survey…” For clarity, what type of participant data were extracted from the household survey? I'm struggling to reconcile the household survey conducted in July – December 2023, and the semi-structured interviews described as part of the Data collection and data instrument sub-section. The study is presented here as a prospective one with the retrospective approach only mentioned in the Limitations section. The authors should explicitly state the study design adopted as part of the methods section and avoid ambiguity.

• Lines 148 – 149, page 7; “…data for the household survey via face-to-face interviews with study participants…” Where were these interviews conducted. I ask this with relation to the privacy of the interviews conducted.

• Line 149, page 7; “…using semi-structured data collection instrument.” Kindly provide further clarity on the semi-structured data collection instrument used. If adapted from a publicly available source, please cite appropriately. If not, kindly provide a template as part of supplementary material for ease of reference.

• Line 182, page 10; “Nigerian Nigeria (13,300 NGN = 30 US Dollars)” This is unclear to me. Are the authors referring to the Nigerian currency?

• Line 237, page 13; “…we obtained verbal informed consent from the participants…” As part of the ethics statement, kindly provide further clarification as to why written informed consent was not possible or required for this study.

• Table 3, page 16; The number of female and male participants in Table 1 and 2 do not correlate. Kindly review all data presented in the manuscript and ensure that they are in fact accurate.

• Lines 371 – 372, page 23; “This interpretation suggests that by inducing a higher perception of COVID-19 severity…” With regards to the recommendations made here and later on in the manuscript, I’m wondering if the authors would consider re-framing this to advocate for context-specific and culturally appropriate education campaigns tailored to the needs of IDPs in order to enhance ownership and informed decision-making on COVID-19 vaccination rather than inducing a higher perception of COVID-19 severity.

• Line 375, page 24; “…communication to shape disease risk reception…” Do the authors mean, "...disease risk perception..."?

Reviewer #2: This study focused on determining the intention of internally displaced persons (IDPs) to accept COVID-19 vaccination and the factors associated with their choice as communicated by the IDPs involved in the study. The authors indicated that about 63.5% of IDPs expressed an intent to accept the COVID-19 vaccine while less than 2/3rd of the IDPs expressed no intent to accept the COVID-19 vaccine. Reasons behind the IDPs choice to accept the COVID-19 vaccine included a perception of COVID-19 as a severe disease and the living of IDPs in official or formal camps while the reasons behind the IDPs choice to reject the COVID-19 vaccine included COVID-19 misconceptions, vaccine safety concerns, did not feel the need or had no reasons at all.

The reviewer believes the overall information presented in the manuscript is important and should be accepted for publication after minor revisions indicating below.

1) The authors needs to re-word the introduction part of the manuscript from line 73 onwards to better reflect the current situation of COVID-19 globally and in Nigeria. The way they have written the introduction portion currently comes across like COVID-19 is still a global pandemic and the world is in lockdown. But COVID-19 pandemic is now properly managed especially in the developing countries.

Hence, the authors need to indicate the current COVID-19 situation globally and most importantly indicate the situation in developing countries especially in Nigeria where the study was conducted.

2) In the study setting, the authors gave a detailed description of the different camps situation aka formal versus informal camps. However, they did not indicate whether the IDPs included and interviewed for the study lived in official or unofficial camps or a mixture of both. The authors should therefore clearly indicate this and include the information in their results section and their study participants and data source section.

3) The authors also indicated that 63.5% of IDPs express an intent to accept COVID-19 vaccination but it is not clearly stated how this percentage was calculated or what numbers were used to generate this percentage as the numbers indicated in Table 3 does not equate to 63.5% of IDPs. Thus, the authors need to specify how they obtained the 63.5% indicated in the manuscript. Also, the authors need to indicate the numbers used to obtain this percentage. Furthermore, the authors need to indicate the percentage of IDPs that express an intent to reject the COVID-19 vaccine.

In Table 3, the percentage of each of the features indicated are calculated based on the numbers of IDPs that express and intent to either accept or reject the COVID-19 vaccine. Hence, in the results text description, the authors need to make this clearer as it is not obvious.

4) In the discussion section, paragraph 3 contains some redundant information (e.g., misconception, vaccine safety concerns, no felt need, etc.) that had already been stated in paragraph 1. The authors need to consolidate the information in the two paragraphs into one paragraph.

5) Again, the authors need to indicate whether the perceived COVID-19 severity and vaccine effectiveness were obtained from IDPs living in formal or informal camps

6) The authors do not clearly state that over 50% of IDPs express an intent to accept the COVID-19 vaccine but rather they try to belittle this data by giving ambigous percentage of the number of IDPs that expressed an intent to reject the vaccine. They do however, provide a good reference of the percentage of IDPs that expressed an intent to accept the COVID-19 vaccine being below the percentage seen in other generalized populations.

The authors are advised to provide clear and unbiased information regarding the percentage value of IDPs that express an intent to accept or reject the COVID-19 vaccine and not play down the fact that over 50% of IDPs did express an intent to take the COVID-19 vaccine.

7) When the authors describe the factors affiliated with the IDPs independent decission to take or reject the COVID-19 vaccine, they need to be very clear that the percentage quoted is based on the number of individuals tabulated in each category (e.g., intention to express the COVID-19 vaccine) and not the number of individuals in the total population.

8) Finally, the authors need to provide a bit more description about their statistically analyses performed for this study.

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Reviewer #1: Yes: Edina Amponsah-Dacosta

Reviewer #2: No

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PONE-D-24-02466R1COVID-19 vaccination intention among internally displaced persons in complex humanitarian emergency context, Northeast NigeriaPLOS ONE

Dear Dr. Gidado,

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.

Please submit your revised manuscript by Jun 30 2024 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: https://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols. Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols.

We look forward to receiving your revised manuscript.

Kind regards,

Sylvester Maleghemi, MD,MSC, DTH&M, MBA

Academic Editor

PLOS ONE

Journal Requirements:

Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice.

Additional Editor Comment:

Dear Authors'

Thank you for your thorough revisions and for addressing most of the concerns the reviewers raised. However, there are a few remaining points from Reviewer 2's comments that require your attention for minor revisions:

Overall Quality:

• The manuscript is well-written, timely, and offers valuable insights into the vaccination intentions of a vulnerable population, which is crucial for informing public health strategies. The statistical analysis is robust and appropriate for the study design.

Major Comments:

1. Clarification of Study Design and Methods:

• The study design and data collection methods need further clarification. Specifically, there should be a clear distinction between the household surveys conducted and the semi-structured interviews. It is also important to specify whether the study was prospective or retrospective and to include precise dates for participant recruitment and study duration.

2. Calculation and Presentation of Statistics:

• The authors should provide detailed information on how the 63.5% intention to accept COVID-19 vaccination was calculated. This includes specifying the numbers and methodology used to derive this percentage, as the numbers in Table 3 do not straightforwardly equate to this figure. Additionally, ensure that the percentage of IDPs who intend to reject the vaccine is also clearly stated in the manuscript.

3. Contextualization of COVID-19 Situation:

• The introduction should be reworded to better reflect the current global and Nigerian context of COVID-19. This should include the current status of COVID-19 as no longer a pandemic and the specific situation in Nigeria, emphasizing how the management of COVID-19 has evolved.

4. Comparison with Other Populations:

• The discussion should include comparisons with similar studies conducted among migrant populations, such as refugees and other displaced groups globally. For instance, comparing the findings with those from a recent systematic review and meta-analysis on vaccine acceptance among migrant populations would provide a broader context and relevance.

Minor Comments:

1. Typographical and Formatting Corrections:

• Line 182: Correct "Nigerian Nigeria" to "Nigerian Naira".

• Line 375: Correct "disease risk reception" to "disease risk perception".

2. Additional Details in Methods:

• Provide more details about the semi-structured data collection instrument, including whether it was adapted from an existing source or developed for this study. If adapted, cite the source; if developed, include a template in the supplementary material.

3. Privacy During Data Collection:

• Indicate where the interviews were conducted, ensuring the privacy and confidentiality of the participants. This is particularly important given the sensitive nature of the information collected.

Specific Revisions Required:

1. Include Weighted Percentage of IDPs Rejecting Vaccine:

• As noted by the reviewer, state the weighted percentage of IDPs intending to reject the COVID-19 vaccine in the section encompassing lines 280-283, similar to how the intention to accept the vaccine is stated.

2. Include Response Text in Methods and Results:

• Incorporate parts of the text from the rebuttal/response to comment 3 of reviewer 2 into the methods section under the data analysis subheading. This should explain the rationale behind the data collection approach and include details on the statistical analysis method. Additionally, include text from the response to comment 5 of reviewer 2 in the appropriate results section.

3. Correct Currency Terminology:

• Correct the terminology in Line 171 to "Nigerian Naira" and ensure this is consistently used throughout the manuscript.

Conclusion:

Overall, the manuscript provides significant contributions to understanding COVID-19 vaccination intentions among IDPs in Northeast Nigeria. By addressing the above comments, the authors can enhance the clarity, accuracy, and impact of their study. These revisions will help ensure the manuscript meets the high standards expected for publication.

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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

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 taking the time to carefully consider the comments and suggestions raised during the first round of review. I have the following final issues which need addressing:

Comment: Line 182, page 10; “Nigerian Nigeria (13,300 NGN = 30 US Dollars)” This is unclear to

me. Are the authors referring to the Nigerian currency?

Response: Yes, NGN is the currency code for Nigerian Naira. We also indicated this in the

footnotes of the respective Tables (Lines 171, 259, 278, and 327 ).

This has still not been revised to Nigerian Naira as raised during the previous review. Please revise this throughout the manuscript where it appears.

Lines 394 - 395, page 24; "Although the safety and effectiveness of COVID-19 vaccine are widely disputed..." To avoid this statement being misconstrued, I would encourage the authors to qualify what they mean by "widely disputed". Does this imply that the scientific expert community is uncertain about the safety and effectiveness of all COVID-19 vaccines or does this refer to the uncertainties prominent among the general public?

Reviewer #2: The authors have greatly revised the manuscript and addressed a large proportion of the raised concerns after reviewing the original manuscript. However, some concerns were not fully addressed and require minor revisions.

The authors did not respond fully to comment (3) of reviewer 2 and should therefore state the weighted % of IDPs that expressed an intent to reject the COVID-19 vaccines in the section encompassing lines 280 - 283 just as they stated for the IDPs who expressed a desire to accept COVID-19 vaccine as indicated in lines 268 - 269 of their revised manuscript. The numbers are already presented in their table so I don't assume it would be difficult to use their statistical analysis method to obtain the requested result.

Also, the authors need to include some of the text in their rebuttal/response to comment (3) of reviewer 2 in the methods section of the revised manuscript text - specifically the data analysis subheading section. The authors should start by explaining simply why they decided to collect the data for this study using a complex approach as it will provide some context to some of the method description in the data analysis section of their revised manuscript before including where appropriate some of their response to comment 3 as indicated above in the revised manuscript methods data analysis section.

Also some of the response text to comment (5) of reviewer 2 should be include in the appropriate results sectionof the revised manuscript text.

Finally, the authors need to correct the error in Line 171 Nigerian Nigeria to Nigerian Naira as indicated in lines 259, 278 and 327.

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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: Edina Amponsah-Dacosta

Reviewer #2: No

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[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.

COVID-19 vaccination intention among internally displaced persons in complex humanitarian emergency context, Northeast Nigeria

PONE-D-24-02466R2

Dear Dr. Gidado,

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.

An invoice will be generated when your article is formally accepted. Please note, if your institution has a publishing partnership with PLOS and your article meets the relevant criteria, all or part of your publication costs will be covered. Please make sure your user information is up-to-date by logging into Editorial Manager at Editorial Manager® and clicking the ‘Update My Information' link at the top of the page. If you have any questions relating to publication charges, please contact our Author Billing department directly at authorbilling@plos.org.

If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org.

Kind regards,

Sylvester Maleghemi, MD, MSC, DTH&M, MBA

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

The manuscript is well-written and clearly articulates the study's background, objectives, methodology, results, and implications. The statistical analysis is robust, and the findings are effectively contextualized within the existing literature. The revisions made in response to previous reviews have significantly improved the clarity and comprehensiveness of the manuscript.

The study design and data collection methods are well-detailed and appropriate for the research questions. The distinction between household surveys and semi-structured interviews is clear, and the study period is well-defined. Explaining the weighted percentage for IDPs intending to accept or reject the COVID-19 vaccine adds transparency to the methodology.

The statistical analysis is sound, using weighted logistic regression models appropriately. The interpretation of adjusted odds ratios is clear and well-supported by the data. Including the rationale for the statistical methods directly in the manuscript enhances transparency and reader understanding.

The authors have successfully addressed previous reviewer comments, particularly regarding comparisons with other populations and clarifications of the study design.

Thank you for the opportunity to review this work.

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: The authors have satisfactorily addressed the queries I raised during the second round of reviews. I have no further comments.

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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: Edina Amponsah-Dacosta

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