PONE-D-20-34952

The cost-effectiveness of oral examination for infants and toddlers

PLOS ONE

Dear Dr. Kim,

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 major changes required by the reviewers is to strengthen the methodology, clarify some of the variables, define costs variables clearly and present the results for costs for defined variables for different regions for reference and control group separately. 

The result section has some missing information and discussion does not follow clearly from the results, 

Overall revision of manuscript addressing the reviewers comments is required. 

Please submit your revised manuscript by May 23 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.

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We look forward to receiving your revised manuscript.

Kind regards,

Charu C Garg, Ph.D.

Academic Editor

PLOS ONE

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Additional Editor Comments:

While the topic is important and interesting, the paper needs some revisions as mentioned by the two reviewers. The reviewers thought that the paper lacks methodological rigor in terms conclusions supporting the findings.

Additionally, some more comments are presented below

Title: There are two major aims of the paper, whereas the title does not refer to the community or regional deprivation at all. The long title could have the name of the country also.

Abstract : needs to be structured and some conclusions are presented even before the results eg. lines 33-35. Conclusions need to follow from the findings. Present the main cost findings in abstract.

Introduction: Please mention in introduction what we know from cost effectiveness studies in other countries and what is the value add for your study or is it for generating evidence in S Korea for what is known for other countries.

Methods: Please explain more clearly the different T-Health index used to measure outcomes for dental health

Line 120: reference is also made of DMFT index, but it does not have  a reference . Also mention how these indices are used to evaluate effectiveness in the paper.

Lines 124-125: Please explain what you mean by social perspective. In the next section, it is mentioned that the indirect and opportunity costs for households was not calculated.

Lines 134-136: please provide the detailed cost items included under the costs borne by health insurance. Are travel costs borne by households?

Line 147 – values are overlapping. Can you explain why and what that means. What are the 5 T-health indices imply in terms of effectiveness – especially when comparing the EDV ad NON-EDV group.

Line 160: what is the cost of the exposed group. Is it the cost per visit, cost per treated child or total costs of all children under the group? Clearly defines these groups.

Line 164: should it be average cost or incremental cost.

Results: clarify most poor and most affluent population – is it bottom 10% or 20% or 25%. Similarly, what top % it is? – table 1 shows how the population is divided for analysis- not clear why it is not 100% for either the EDV or the non-EDV group under any CDI score district.

Also not clear what is the n from which the % are calculated in table 1. Please give clearly the numbers under each group and for each variable considered.

Can you please explain the interpretation of values in table 2 with respect to different T-Health indices?

Before the results for ICER, the results should present a section on costs separately for EDV and Non EDV for different CDI regions. You mention societal costs in methods. What are the costs to the society for treating children with EDV and NON-EDV.

Discussion: Line 230: it should be cost effectiveness.

The discussion does not follow from results. Present the main results and then discuss in context of how these findings collaborate with what is known from literature.

Lines 233-255 – should follow from results. Costs are not mentioned separately for EDV and Non-EDV per dental visit for child. Will be useful to get the costs per treated child which would take into account higher no. of visits for children under EDV.

The discussion does not clearly specify dental costs of what is being considered in different places – eg. Line 261.

Line 267 – OECD data for 2013 is quoted. OECD at a glance will have much later figures. Otherwise also in introduction and discussion, several old references are used. Please try to update those.

Add strengths and limitations of the study. Also have the conclusion follow the results and discussion and not a generic conclusion.

Some of the variables mentioned in the supplementary information in in Korean. Please provide English translation.

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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: Partly

Reviewer #2: Partly

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

Reviewer #1: No

Reviewer #2: No

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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: Comment: Kasahun Girma Tareke

The authors conducted a research entitled “The cost-effectiveness of oral examination for infants and toddlers”. The research is a very interesting work. However, there is a need to make amendment of important parts before accepted for publication. Here find the suggested comments to improve the paper.

Abstract

1. Please make partition for background, methods, results and conclusions.

1.1. Make your methods clear (i.e., sample size for each cases and controls, how you calculated the sample size, sampling technique, methods of data extraction from the data base, data analysis, etc.)

1.2. Make your results clear based on your research objective (s)/question (s). The result section seems like conclusions. Put the numeric/figurative findings for each of the findings.

1.3. Make your conclusions consistent with results. This might be corrected or becomes clear once you make correction of presentation of research findings.

Introduction

1. Good! However, make your research aims consistent with your title; given that the title only focused on cost-effectiveness but not included the first purpose of your study.

Materials and method

1. Please switch to “Methods”.

2. Please give descriptions of your study area/setting, and also the description of the project being implemented since 2007. You have mentioned that “The OEIT is categorized into three age groups 75 as follows: the 1st group is 18-24 months of age, the 2nd group is 42-48 months of age, and the 76 3rd group is 54-60 months of age.” Please specify the type of interventions done for each group.

3. Study design: It is good that you mentioned the study design. However, define the cases and controls clearly.

4. Study populations: It is not clear the number of population among cases and controls. Therefore, please specify it.

5. Sampling and sample size calculation: Your study lacks any information about the samples, calculation formulas, sampling techniques, procedures, etc.

6. Eligibility criteria??? Think of secondary data source.

7. Data analysis: It is not clear about the software you were used to clean, enter or analyzed the data. Other, the type of cost-analysis you have done is not consistent with your title. Your title only focused on one of the cost-analysis; cost-effective analysis.

8. Please make a measurement for your variables (cost-effectiveness, cost-benefit, and cost utility, cost, effectiveness, etc.)

9. Result: Good but you had not presented findings for the research purpose 1 presented on introduction section. Clearly show it. Also not presented according to cost-effectiveness, cost-benefit and cost-utility.

10. Discussion: Please delete the first two sentences of discussion and incorporate it somewhere in the introduction section. Write your pertinent findings as a first paragraph of discussion, and discuss them each by each in the consecutive paragraphs. The third paragraph seems like conclusion. What was your base to say cost-effective at this rudimentary stage? Make your study findings and discussion consistent. On line 271 of your paper, you have discussed that the cost-effectiveness of the ICER in the most deprived areas compared to affluent areas was approximately 1.6 times higher on 272 averages. But, you had not put the odds ratio for your findings. Therefore, please amend your result section incorporating the odds ratio, P-value and confidence intervals.

11. Please add strength and limitations of the study. I think it might have limitations since you had used a secondary data or retrospective cohort study.

12. Conclusions: Make a label “conclusions”. Make consistent with your objectives, pertinent findings and discussions.

13. Please define the abbreviations

14. Declerations????

15. References: You had used too old references. Please try to discuss your findings with the updated research findings.

Reviewer #2: Paper is well written but lack methodological rigour. It is not clear to me in what perspective health economic evaluation is done. Author mentioned social perspective, but in paper it does not reflect in terms of loss of productivity of parents who care for their children in lieu of using dental services. The ICER is not presented well. I can't make out any thing from graphs representing negative ICER bars. The paper clearly lack focus in terms of analysis, costs and benefits. The authors need to present cost-effectiveness overall and then look by level of deprivation. The deprivation cut-off levels are arbitrary and to nullify it it should be use tertile or quartie or quintile break-up.

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Reviewer #1: Yes: Kasahun Girma Tareke

Reviewer #2: Yes: Anil Gumber

[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.]

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Attachments

Attachment

Submitted filename: Reviewer comment.docx

PONE-D-20-34952R1The cost- effectiveness of early dental visit in infants and toddlers focused on regional deprivation in Korea: A retrospective cohort studyPLOS ONE

Dear Dr. Kim,

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. While the paper has been revised and submitted again as a fresh paper,  a rebuttal letter with specific answers to the reviewers comment's and how they were taken into account should have been provided. In fact the second reviewer still has several additional methodological comments and suggestions and would not like to accept the paper in current form.  we request the authors to take those into account and provide specific answers to each of the reviewers comment, as to how those were addressed.Please also provide answers to the comments that were given in version 1 of the comments.

Please submit your revised manuscript by Jan 18 2022 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,

Charu C Garg, Ph.D.

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 Comments (if provided):

Line 52: US data reported is quiter old. Can it be updated?

line 83: PLease the sentence construction. Seems like some missing information.

Lines 136 and 145 are repeated…. can be avoided

Tsble 1 - check quintiles

DMFT index values have not been explained in the methods, so not clear why it is contradictory to expectations in Line 269.

THe third effectiveness variable  - missing teeth  - has not been presented in the results.If not to be used, must be mentioned upfront in the methods.

please read thoroughly to correct the grammar. Several sentences do not read well.

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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)

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: (No Response)

Reviewer #2: Partly

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

Reviewer #1: (No Response)

Reviewer #2: No

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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: (No Response)

Reviewer #2: No

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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: (No Response)

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: (No Response)

Reviewer #2: see my comments to the editor as authors have not fully addressed reviewers comments. They have not prepared response to reviewers.

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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: Kasahun Girma Tareke

Reviewer #2: Yes: Anil Gumber

[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-20-34952R2

The cost- effectiveness of early dental visit in infant and toddlers focused on regional deprivation in South Korea: A retrospective cohort study

PLOS ONE

Dear Dr. Kim,

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.

There are few language issues and minor changes in some places in the attached document to bring more clarity to the paper. Some of the earlier edits suggested in the tables have not been made. For example 5 classes have been made and the authors still refer them to quartiles instead of quintiles.

Please submit your revised manuscript by Jun 19 2022 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,

Charu C Garg, Ph.D.

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 Comments:

Thank you for making changes as per the comments by the reviewers. Please see the attached copy for some minor clarifications and edits required for the document.

[Note: HTML markup is below. Please do not edit.]

Reviewers' comments:

[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: PONE-D-20-34952_R2-CG comments.pdf

The cost- effectiveness of early dental visit in infants and toddlers focused on regional deprivation in South Korea: A retrospective cohort study

PONE-D-20-34952R3

Dear Dr. Kim,

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 for payment will follow shortly after the formal acceptance. To ensure an efficient process, please log into Editorial Manager at http://www.editorialmanager.com/pone/, click the 'Update My Information' link at the top of the page, and double check that your user information is up-to-date. If you have any billing related questions, 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,

Charu C Garg, Ph.D.

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

There a a few minor editorials still required eg. line 38 - a word - "weight" seem to be missing. The editorial team may please see for correctness of grammar. 

Reviewers' comments: