Prevalence of clinically significant refractive error in children in Europe: Systematic review and meta-analysis

Megan Doyle; Aoife O’Donnell; Síofra Harrington; Veronica O’Dwyer; Michael Moore

doi:10.1371/journal.pone.0335666

Peer Review History

Original SubmissionMay 16, 2025
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Is the manuscript technically sound, and do the data support the conclusions? Reviewer #1: Partly Reviewer #2: Yes ******** 2. Has the statistical analysis been performed appropriately and rigorously? -->?> Reviewer #1: Yes Reviewer #2: Yes ****** 3. Have the authors made all data underlying the findings in their manuscript fully available??> The PLOS Data policy Reviewer #1: Yes Reviewer #2: Yes ****** 4. Is the manuscript presented in an intelligible fashion and written in standard English??> Reviewer #1: Yes Reviewer #2: Yes ****** Reviewer #1: Dear Authors, I have few concerns regarding the data accuracy. You included in your analysis a recent study from Russia (Bibkov&All, 2023) on a very consistent group of subjects. I red the abstract of this study and actually there is no mention in this study about Hyperopia incidence (in your table appears as being 11.1%) because it is a study focused exclusively on Myopia. From the clinical point of vu, I think your analysis is expanded on a very large period and the cohorts included in the studies are very heterogeneous and the large groups influence the final statistics. Reviewer #2: General comments: The article is well written, with a clearly defined PICO framework and well-articulated aims. The methodology meets the criteria for a meta-analysis, with appropriate use of plots and figures to present the findings. The conclusions are clearly stated and consistent with the results. Minor comments : 1- Introduction, line 50 Consider specifying “uncorrected refractive error” instead of “refractive error” to be more precise, as the burden on visual impairment is primarily due to uncorrected cases. 2- Introduction, line 57 The first sentence could be rephrased for clarity. For example: “While severe refractive error carries greater individual risk, the broader public health burden stems from the vast number of people with low to moderate refractive error, particularly myopia.” ****** what does this mean? ). If published, this will include your full peer review and any attached files. If you choose “no”, your identity will remain anonymous but your review may still be made public. Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy Reviewer #1: No Reviewer #2: No ******** [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". 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Revision 1
24 Sep 2025 Author Response Dr Emily Chenette, PhD Editor-In-Chief PLoS One 11th September 2025 Dear Doctor Chenette, Thank you for the opportunity to submit our revised manuscript entitled "Prevalence of Clinically Significant Refractive Error in Children in Europe: Systematic Review and Meta-Analysis" for consideration for publication in PLoS One. The authors thought the feedback was positive, with helpful pointers for the paper. The authors appreciate the time and effort the reviewers have dedicated to providing valuable feedback on the manuscript. The authors have been able to incorporate changes to reflect the suggestions provided by the reviewers. In summary, having considered the comments in some detail, the following amendments have been made: 1. Two short sections have been added to clarify points highlighted by Reviewer 1. 2. Lines 50-51, and lines 57 have been rephrased as per Reviewer 2 comments. The authors have highlighted the changes within the manuscript using tracked changes. Here is a point-by-point response, including edits (italicised) to the reviewers' comments and concerns (in boldface). Reviewer: 1 Dear Authors, I have few concerns regarding the data accuracy. You included in your analysis a recent study from Russia (Bikbov et al., 2023) on a very consistent group of subjects. I read the abstract of this study and actually there is no mention in this study about Hyperopia incidence (in your table appears as being 11.1%) because it is a study focused exclusively on Myopia. From the clinical point of view, I think your analysis is expanded on a very large period and the cohorts included in the studies are very heterogeneous and the large groups influence the final statistics. The authors thank the reviewer for their thoughtful comments and the opportunity to clarify these points. With regard to the concern about the Russian study by Bikbov et al.,1 while hyperopia prevalence is not mentioned in the abstract, it is reported in the main body of the paper. Specifically, in the results section (page 594), the authors state: “… and the prevalence of hyperopia (>0.50 D) was 524/4737 (11.1%; 95% CI 10.2–12.0%).” The value reported in Table 2 of the current manuscript accurately reflects this finding. On the issue of study periods, there is currently limited refractive error prevalence data available for children in Europe. Restricting the timeframe would have reduced the evidence included in the current analysis. Previous meta-analyses of myopia prevalence have adopted similar inclusion periods; for example, Liang et al.2 analysed studies from 1990-2023, while Hashemi et al.3 included data from 1990-2016. The approach used in the current meta-analysis therefore aligns with established practice and extends the evidence base by incorporating refractive error types beyond myopia. This was clarified in the manuscript as follows: 2.1 Literature Search Strategy, Lines 87-92: “To maximise the available evidence, studies published from 1 January 2000 to 30 September 2024 were included. This broad timeframe was consistent with previous prevalence meta-analyses and ensured the inclusion of recent, methodologically robust studies while allowing adequate data coverage for European children, where studies remain limited.5,6,10” The authors agree with the reviewer that heterogeneity is an inherent feature of prevalence meta-analyses, reflecting variations in study populations, geography, methodology, sample size, and timeframes.4 To address this, a random-effects model was applied, which is designed to account for both within- and between-study variability.5 Additionally, Freeman-Tukey double arcsine transformation and leave-one-out sensitivity analyses were employed to reduce the influence of outlying prevalence estimates and to ensure that larger studies did not disproportionately affect the pooled results.6 Taken together, these methodological choices follow established best practices and provide robust estimates despite the unavoidable heterogeneity in the available data. This was clarified in the manuscript as follows: 4.8 Strengths, Limitations and Future Directions, Lines 445-447: “The broad timeframe and heterogeneous cohorts may have influenced the pooled estimates. This is an inherent feature of prevalence meta-analyses, and the use of a random-effects model with sensitivity analyses was intended to account for this.69-71” References: 1. Bikbov MM, Kazakbaeva GM, Fakhretdinova AA, Tuliakova AM, Iakupova EM, Panda-Jonas S, et al. Prevalence and associated factors of myopia in children and adolescents in Russia: the Ural Children Eye Study. BJO. 2024;108:593-598. 2. Liang J, Pu Y, Chen J, Liu M, Ouyang B, Jin Z, et al. Global prevalence, trend and projection of myopia in children and adolescents from 1990 to 2050: A comprehensive systematic review and meta-analysis. BJO. 2024;109(3):362-71. 3. Hashemi H, Fotouhi A, Yekta A, Pakzad R, Ostadimoghaddam H, Khabazkhoob M. Global and regional estimates of prevalence of refractive errors: Systematic review and meta-analysis. J Curr Ophthalmol. 2018;30:3–22. 4. Migliavaca CB, Stein C, Colpani V, Barker T, Ziegelmann P, Munn Z, et al. Meta-analysis of prevalence: I2 statistic and how to deal with heterogeneity. Res Synth Methods. 2022;13(3):363-367. 5. Borenstein M, Hedges LV, Higgins JPT, Rothstein HR. Random-Effects Model. In: Introduction to Meta-Analysis. Wiley;2009:69-75. 6. Barendregt JJ, Doi SA, Lee YY, Norman RE, Vos T. Meta-analysis of prevalence. J Epidemiol Community Health. 2013;67:974-978. Reviewer: 2 General comments: The article is well written, with a clearly defined PICO framework and well-articulated aims. The methodology meets the criteria for a meta-analysis, with appropriate use of plots and figures to present the findings. The conclusions are clearly stated and consistent with the results. The authors thank the reviewer for their positive feedback. Minor comments: 1- Introduction, line 50 Consider specifying “uncorrected refractive error” instead of “refractive error” to be more precise, as the burden on visual impairment is primarily due to uncorrected cases. The authors thank the reviewer for this suggestion. The introduction has been updated to reflect this as follows: Lines 50-51: “Uncorrected refractive error is a leading cause of visual impairment worldwide and a growing public health concern, particularly in children.” 2- Introduction, line 57 The first sentence could be rephrased for clarity. For example: “While severe refractive error carries greater individual risk, the broader public health burden stems from the vast number of people with low to moderate refractive error, particularly myopia.” The authors thank the reviewer for their comment. The introduction has been updated to incorporate this as follows: Lines 57-59: “While severe refractive error carries greater individual risk, the broader public health burden stems from the vast number of people with low to moderate levels of refractive error, particularly myopia.” Editor Comments: The manuscript has been updated to follow the style requirements. The competing interests and funding statements have been updated as requested. Figure 4 and S3 have been recreated using public domain data which is cited in the figure legend. The authors thank the editorial board and the reviewers for their constructive comments. We appreciate your input, which has improved the paper's clarity and readability. Yours sincerely, Michael Moore (corresponding author), Centre for Eye Research Ireland, School of Physics, Clinical & Optometric Sciences, Technological University Dublin, City Campus, Grangegorman, Dublin, Ireland. Email: michael.moore@tudublin.ie Attachments Attachment Submitted filename: Letter of Response to Reviewers.docx https://doi.org/10.1371/journal.pone.0335666.r002
15 Oct 2025 Decision Letter - Neelam Pawar, Editor Prevalence of Clinically Significant Refractive Error in Children in Europe: Systematic Review and Meta-Analysis PONE-D-25-23846R1 Dear Dr.Michael Moore 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. For questions related to billing, please contact billing support . 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, Neelam Pawar Academic Editor PLOS ONE Additional Editor Comments (optional): Reviewers' comments: https://doi.org/10.1371/journal.pone.0335666.r003
Formally Accepted
Acceptance Letter - Neelam Pawar, Editor PONE-D-25-23846R1 PLOS ONE Dear Dr. Moore, I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now being handed over to our production team. At this stage, our production department will prepare your paper for publication. This includes ensuring the following: * All references, tables, and figures are properly cited * All relevant supporting information is included in the manuscript submission, * There are no issues that prevent the paper from being properly typeset You will receive further instructions from the production team, including instructions on how to review your proof when it is ready. Please keep in mind that we are working through a large volume of accepted articles, so please give us a few days to review your paper and let you know the next and final steps. Lastly, if your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. 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. You will receive an invoice from PLOS for your publication fee after your manuscript has reached the completed accept phase. If you receive an email requesting payment before acceptance or for any other service, this may be a phishing scheme. Learn how to identify phishing emails and protect your accounts at https://explore.plos.org/phishing. If we can help with anything else, please email us at customercare@plos.org. Thank you for submitting your work to PLOS ONE and supporting open access. Kind regards, PLOS ONE Editorial Office Staff on behalf of Dr. Neelam Pawar Academic Editor PLOS ONE https://doi.org/10.1371/journal.pone.0335666.r004

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