Age-Matched Comparative Analysis of Binocular Vision Anomalies among Children with Dyslexia in Northern Nigeria
, Mizhanim Mohamad Shahimin 1, Bariah Mohd-Ali 1, Eki Oghre 5, Ferial M. Zeried 6 and Uchechukwu Levi Osuagwu 3,*Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsThe manuscript presents the results from a thorough examination of the visual acuity and binocular vision of children with dyslexia and an age-matched control group in Nigeria. The tests are accurately performed, and the diagnostic criteria match other studies.
Several studies investigate the binocular vision dysfunctions in dyslexia in different countries. This study fills a gap and would allow to access the demographic extent of the incidence and prevalence of binocular vision problems in children with dyslexia and children with no reading problems. However, it would be good to compare not only the data for the dyslexic group with the results of similar studies from other countries but also the data for the control group. Such comparisons may help in evaluating the contributions of other factors - such as environmental, genetic, and ethnic influences - to the occurrence of binocular dysfunction and reading disabilities.
During the discussion, the authors examined the prevalence of convergence insufficiency in dyslexic children in studies conducted in other countries. However, their own study revealed no such deficiency in a pure form in the dyslexic group and it was only found in the control group. This disparity requires further discussion.
It would be interesting to present the data for the accommodation insufficiency separately as a boxplot to see more clearly the distribution of the individual values in both the dyslexic and control groups.
The most important issue is that the tables providing the methodological details and results are missing. This omission hinders a proper evaluation of the study and its conclusions.
Author Response
Reviewer’s comments
Dear Reviewer,
We appreciate your effort in reviewing our study and giving a constructive feedback to help us improve the quality of our study. We have responded to all comments accordingly.
First reviewer’s comment
- Comment.
The manuscript presents the results from a thorough examination of the visual acuity and binocular vision of children with dyslexia and an age-matched control group in Nigeria. The tests are accurately performed, and the diagnostic criteria match other studies.
Several studies investigate the binocular vision dysfunctions in dyslexia in different countries. This study fills a gap and would allow to access the demographic extent of the incidence and prevalence of binocular vision problems in children with dyslexia and children with no reading problems. However, it would be good to compare not only the data for the dyslexic group with the results of similar studies from other countries but also the data for the control group. Such comparisons may help in evaluating the contributions of other factors - such as environmental, genetic, and ethnic influences - to the occurrence of binocular dysfunction and reading disabilities.
Response
Thank you for your suggestion.
The findings have also been compared with the findings of control group in other studies (line 324 to 328).
- Comment.
During the discussion, the authors examined the prevalence of convergence insufficiency in dyslexic children in studies conducted in other countries. However, their own study revealed no such deficiency in a pure form in the dyslexic group and it was only found in the control group. This disparity requires further discussion.
Response
It has been modified as suggested (line 348 to 356).
- Comment.
It would be interesting to present the data for the accommodation insufficiency separately as a boxplot to see more clearly the distribution of the individual values in both the dyslexic and control groups.
Response
Accommodative insufficiency is a categorical data, it might not be possible to plot a Boxplot for categorical data. However, an alternative for boxplot has been provided in form of a bar chart to show the distribution between the two groups (Figure 3).
- Comment.
The most important issue is that the tables providing the methodological details and results are missing. This omission hinders a proper evaluation of the study and its conclusions.
Response
All tables have been provided as suggested (table 1 and 2).
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsI read with interest the manuscript entitled “Age-Matched Comparative Analysis of Binocular Vision 2 Anomalies among Children with Dyslexia in Northern Nigeria”. It falls within my area of expertise, and I am familiar with the field and literature related to this manuscript.
In this paper, the authors have compared the visual abilities between two groups: a dyslexic group and a control group. Evaluations were performed in terms of direct comparison or the prevalence of anomalies. The main aim of the manuscript is interesting and compatible with clinical needs. The sample size is adequate for comparison.
The overall evaluation of the manuscript is positive. There are only a series of minor points to improve to reach a perfect publication level. They are listed below.
General
As a matter of consistency, I suggest reporting accommodative, binocular, and oculomotor anomalies in this order throughout the entire manuscript.
To avoid confusion, do not report accommodation insufficiency within binocular anomalies.
The reference suggested should be taken into consideration.
In particular, please consider in deep the book of Scheiman & Wick (2019 or previous editions) in which the scheme of test and analysis was reported. Chapter 14 of the fourth edition presents an interesting scheme in which the area of visual efficacy has been divided into three components: accommodative, binocular, and ocular movements. This is useful to structure testing and analysis.
Abstract.
Make it shorter
Move the description of participants to the method section.
The lines 24-26 should be shorted describing "visual acuity, refraction, accomodative, binocular and oculomotor skills were examined" or something similar.
Results should be shorted avoiding acronyms if not necessary.
Introduction
Rather than report the "relationship between dyslexia and vision anomalies", discuss the prevalence of visual anomalies in this group.
Line 62: "2010" repeated.
Methods
In the power analysis, report the sample needs for a direct group comparison or a sensitivity analysis with the sample collected.
Tables are lacking, so another round of revision is absolutely required for a comprehensive review.
I suggest a simple table describing the mean (SD) results of the two groups with a third column for statistical comparison.
Order the test in the following way:
- General examination (external eye examination).
- VA
- Accomodative skills
- Binocular skills including vergence and phorias
- Oculomotor skills (DEM)
How were symptoms collected?
Data Collection Procedure should be renamed "Procedure" and a paragraph "Tests" should be added.
Visual acuity must be analysed in logMAR scale, even if it was collected in decimal scale.
DEM test is a paper-based oculomotor test aimed at giving an indirect measure of eye movement in a reading-like condition. Use this sentence to define better DEM.
Do not separate DEM in the four classifications. Instead compare RAW values and/or percentiles.
Phoria should be included in the binocular areas of tests
Are vergence assessed firstly base-out or firstly base-in? Refer to Rosenfield et al., (1995).
In the accommodative section, separate it in the section
- Amplitude
- Accomodative response (dynamic retinoscopy)
- Accomodative facility
The respective anomalies need to be defined below each test definition.
Line 210. Since not all data are on BV, remove them.
To improve the quality of the results, perform two sections of analyses: the first is a direct comparison of each visual skill between groups, while the second is the prevalence of anomalies and their comparison in each group.
Results
Add missing tables
Report analyses on VA on logMAR scales
Results of oculomotor skills are lacking.
Separate results as indicated above
Try to figure out figure 1 using 2 pie charts
Discussion
Describe the limitations of the study taking into account not a general population of children, but those specifically visiting the hospital.
Line 310, fix the typo error.
Importantly, linked to the first point, repeat several times that the prevealence is in a hospital or optometric clinic, consequently it cannot be generalised.
Describe the differences between the groups based on both modalities of analysis listed above.
Line 294 discuss the work of the CITT-ART studies ()
Line 316 reading is not a visual function, is a cognitive abilirties linked to different visual and cognitive skills. Amend the sentence accordingly.
References
1. Facchin, A. (2021). Spotlight on the developmental eye movement (DEM) test. Clinical Optometry, 73-81.
2. Scheiman, M., & Wick, B. (2008). Clinical management of binocular vision: heterophoric, accommodative, and eye movement disorders. Lippincott Williams & Wilkins.
Author Response
Reviewer 2 comments
Dear Reviewer,
We appreciate your effort in reviewing our study and giving a constructive response to help us improve the quality of our study. We have responded to all comments accordingly.
The overall evaluation of the manuscript is positive. There are only a series of minor points to improve to reach a perfect publication level. They are listed below.
Comment.
General
1. As a matter of consistency, I suggest reporting accommodative, binocular, and oculomotor anomalies in this order throughout the entire manuscript.
To avoid confusion, do not report accommodation insufficiency within binocular anomalies.
The reference suggested should be taken into consideration.
In particular, please consider in deep the book of Scheiman & Wick (2019 or previous editions) in which the scheme of test and analysis was reported. Chapter 14 of the fourth edition presents an interesting scheme in which the area of visual efficacy has been divided into three components: accommodative, binocular, and ocular movements. This is useful to structure testing and analysis.
Response
The changes have been made as suggested across board.
Comment
Abstract.
Make it shorter
Response
The abstract has been shortened and description of participants moved to method as suggested. Please see line 18 to 44.
Comment
The lines 24-26 should be shorted describing "visual acuity, refraction, accommodative, binocular and oculomotor skills were examined" or something similar.
Response
It has been edited as suggested (line 27 to 28).
Comment
Results should be shorted avoiding acronyms if not necessary.
Response
The result has been shortened as suggested (line 31 to 40).
Comment
Introduction
6. Rather than report the "relationship between dyslexia and vision anomalies", discuss the prevalence of visual anomalies in this group.
Response
The prevalence of the visual anomalies has been added as suggested (line 63 to 68).
Comment
Line 62: "2010" repeated.
Response
It has been deleted. Dusek et al., 2010.
Comment
Methods
In the power analysis, report the sample needs for a direct group comparison or a sensitivity analysis with the sample collected.
Response
The sample needed for a direct group comparison has been added as suggested (line 102 to 103).
Comment
Tables are lacking, so another round of revision is absolutely required for a comprehensive review.
I suggest a simple table describing the mean (SD) results of the two groups with a third column for statistical comparison.
Response
The table has been added as suggested (tables 1 to 4).
Comment
Order the test in the following way:
- General examination (external eye examination).
- VA
- Accomodative skills
- Binocular skills including vergence and phorias
- Oculomotor skills (DEM)
Response
The tests has been arranged accordingly, as reported in table 1 and 4.
Comment
How were symptoms collected?
Response
Symptoms were assessed with a validated questionnaire developed from previous studies. (Line 127 to 135).
Comment
Data Collection Procedure should be renamed "Procedure" and a paragraph "Tests" should be added.
Response
It has been renamed as suggested (line 114).
Comment
Visual acuity must be analysed in logMAR scale, even if it was collected in decimal scale.
Response
Visual acuity has been analysed in logMAR scale and added in table 3.
Comment
DEM test is a paper-based oculomotor test aimed at giving an indirect measure of eye movement in a reading-like condition. Use this sentence to define better DEM.
Response
DEM has been modified as suggested please (line 195 to 196).
Comment
Do not separate DEM in the four classifications. Instead compare RAW values and/or percentiles.
Response
It has been compared accordingly as shown in table 4. The raw values were compared and presented in Mean SD in Table 4.
Comment
Phoria should be included in the binocular areas of tests
Response
It has been added as suggested across board.
Comment
Are vergence assessed firstly base-out or firstly base-in? Refer to Rosenfield et al., (1995).
Response
Base in was assessed before base out because of the convergence effect of base out.
- Comment
In the accommodative section, separate it in the section
- Amplitude
- Accomodative response (dynamic retinoscopy)
- Accomodative facility
Response
It has been separated as suggested.
- Comment
The respective anomalies need to be defined below each test definition.
Response
They have been defined in table 2.
- Comment
Line 210. Since not all data are on BV, remove them.
Response
It has been modified as suggested.
- Comment
To improve the quality of the results, perform two sections of analyses: the first is a direct comparison of each visual skill between groups, while the second is the prevalence of anomalies and their comparison in each group.
Response
It has been modified as suggested in figure 1, 2 and table 4.
Results
22. Comment
Add missing tables
Response
All tables have been added.
Comment
Report analyses on VA on logMAR scales
Response
It has been added as suggested in table 3.
- Comment
Results of oculomotor skills are lacking.
Response
Oculomotor skill results have been added in table 4.
- Comment
Separate results as indicated above
Try to figure out figure 1 using 2 pie charts
Response
It has been modified as suggested in figure 1, 2 and 3.
Discussion
26. Comment
Describe the limitations of the study taking into account not a general population of children, but those specifically visiting the hospital.
Response
It has been modified as suggested (line 363 to 365).
Comment
Line 310, fix the typo error.
Response
It has been corrected to general (Limitation of study)
Comment
Importantly, linked to the first point, repeat several times that the prevalence is in a hospital or optometric clinic, consequently it cannot be generalised.
Describe the differences between the groups based on both modalities of analysis listed above.
Response
It has been modified (line 350 to 352).
29. Comment
Line 294 discuss the work of the CITT-ART studies ()
Response
It has been added in line 329 to 341.
Comment
Line 316 reading is not a visual function, is a cognitive abilirties linked to different visual and cognitive skills. Amend the sentence accordingly.
Response
It has been corrected as suggested.
Author Response File: Author Response.pdf
