High prevalence of gastroschisis in Brazilian triple side border: A socioenvironmental spatial analysis

This research investigated the spatial association between socioenvironmental factors and gastroschisis in Brazilian triple side border. A geographic analysis for gastroschisis prevalence was performed considering census sector units using Global Moran Index, Local Indicator of Spatial Association Analysis and Getis Ord statistics. Sociodemographic factors included rate of adolescent and parturients over 35 years; population with no income and above 5 minimum wages; rate of late prenatal; and proximity to power transmission lines. Logistic regression models were applied to verify the association between socio-environmental factors and prevalence of gastroschisis. No global spatial correlation was observed in the distribution of gastroschisis (Moran´s I = 0.006; p = 0.319). However, multiple logistic regression showed census sectors with positive cases had higher probability to power transmission lines proximity (OR 3,47; CI 95% 1,11–10,79; p = 0,031). Yet, spatial scan statistic showed low risk for gastroschisis in southern city region (OR = 0; p = 0.035) in opposite to power transmission lines location. The study design does not allow us to attest the causality between power transmission lines and gastroschisis but these findings support the potential exposure risk of pregnant to electromagnetic fields.

Observations regarding each manuscript section are below.

1) Title
It is specific, descriptive, and draws attention to the present question.
No recommendations in this section.

2) Abstract
It is a non-structured abstract that describes the study's primary objective, explains the method's principal points, and shows the main results and conclusion.
No recommendations in this section.

3) Background
The authors summarized the gastroschisis problem very well; nevertheless, PREVALENCE is the usual term in the medical literature when referring to a frequency measure of any congenital disease, not

A) Study design, setting, and population
Line 74 -The term newborn covers the population of live births and stillbirths. As SINASC uses only the live births population, it would be better to replace the term to avoid confusion.
Line 74 -Is not the six years period (2012 -2017) short for this analysis? Publications numbers 27 -30 in the REFERENCES section present a study period that varies from 7 to 33 years.
The alteration of the term and the explanation for the six-year period are the recommendations in this section.

My recommendation in this section is to:
-Alter the statement in "Data Availability": NOto YES, and refer to the DATASUS WEBSITE.
-Alter the statement that "Data cannot be shared publicly" because they already are public. In "Describe where the data may be found……appropriate details." -The technical details should be expanded and clarified to ensure that readers understand precisely the steps made. It is not only to export the SINASC data to an Excel spreadsheet; TABWIN should be used first.
-The technical details should be expanded and clarified to ensure that readers precisely understand the steps to obtain all the SINASC and IBGE data.

C) Power Transmission Lines
No recommendations in this section.

D) Data analysis
The alteration to PREVALENCE instead of the term INCIDENCE as recommended before.

E) Global Moran's Index
No recommendations in this section.

F) Local indicator of spatial association analysis
No recommendations in this section.

G) Getis-Ord statistics
No recommendations in this section.

H) Spatial scan statistic
No recommendations in this section.

I) Logistic regression
Line 208: The authors used a distance of 850 meters between the centroid of the census sector to the closest point in PTL as an independent variable. No other paper in the REFERENCE section uses this distance (Ref 10: 600m,Ref 29: <200m,>600m,Ref 30: 500m), and in the DISCUSSION section line 272, the authors also describes the distances. So, the question is, why did the authors use 850m as standard?
The authors should clarify and expand the technical details to a better understanding.
Line 220: The authors could create another subsection entitle: Ethics Review to present the Ethics data from Plataforma Brasil, apart from Logistic regression. While the study appears to be sound, the language is unclear, making it difficult to follow. Please advise the authors to work with a writing coach or copyeditor to improve the text's flow and readability, principally in the Discussion's first paragraph.

7) Limitation
No recommendations in this section.

8) Conclusion
No recommendations in this section.

9) Acknowledgments
No recommendations in this section.

10) References
No recommendations in this section.
Overall, the manuscript's idea is outstanding. A major revision will be required, and an English revision from a Native speaker or a writing editing service. Some points must be better explained to clarify and give a better understanding to the readers. Sincerely M.G.C -M.D, Ph.D