PONE-D-23-04326The impact of angles of insonation on left and right ventricular global longitudinal strain estimation in fetal speckle tracking echocardiography.PLOS ONE

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Additional Editor Comments:

Reviewer 1:

The study is interesting and written comprehensively enough to understand. The objectives, and methodology have provided adequately that the paper does offer enough details to reproduce the experiments.

No major revision from my side. However, there are few comments.

1) In abstract, under objectives, first few lines seem background. So should come under heading of it.

2) The objective need to be revised (as primary and secondary) as author studied the Semmler et al. definition separately by sensitivity analysis.

3) Similarly in abstract, under method, the last lines need to be revised as creating confusion to reader, please define clearly, why and to whom you did sensitivity analysis?

4) In manuscript, under method it was mentioned that ‘Women who developed gestational diabetes or hypertensive pregnancy disorders, and those who gave birth to a neonate with a birth weight below the 10th percentile or with congenital or genetic abnormalities were excluded from the analysis as these factors may influence myocardial deformation values’.

I did not find any point where it is mentioned that clips were selected after the birth of baby. If this is so, please mention it otherwise remove this statement.

5) Under data acquisition, these lines seem accessary and should be removed ‘Adequate quality fetal heart clips can be achieved by an appropriate setting of the region of interest (ROI)8, and optimal settings of depth, width, and zoom box help to achieve maximum FR, while not critically degrading image quality minimizing the impact of potential speckle anisotropy on fetal 2D-STE.

Add objective points on which you checked image quality, via in a table or here in text.

6) Under angle of Insonation 2nd paragraph needs to be rephrased.

7) Results are not written in a very structured manner, please revise it.

Reviewer 2:

The article is very well conceptualized. the authors have explained the process of speckle tracking frame rate and GLS which are actually not easy to understand in simplified way. They have already discussed their limitation in terms of retrospective data and unavailability of normal values, but articles with scientific content like these should be encouraged as these will set the trend for more work and normal standards. i must congratulate the authors on their extremely important and hard work.

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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: Yes

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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: Yes

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: Manuscript ID: PONE-D-23-04326

The impact of angles of insonation on left and right ventricular global longitudinal strain estimation in fetal speckle tracking echocardiography.

The study is interesting and written comprehensively enough to understand. The objectives, and methodology have provided adequately that the paper does offer enough details to reproduce the experiments.

No major revision from my side. However, there are few comments.

1) In abstract, under objectives, first few lines seem background. So should come under heading of it.

2) The objective need to be revised (as primary and secondary) as author studied the Semmler et al. definition separately by sensitivity analysis.

3) Similarly in abstract, under method, the last lines need to be revised as creating confusion to reader, please define clearly, why and to whom you did sensitivity analysis?

4) In manuscript, under method it was mentioned that ‘Women who developed gestational diabetes or hypertensive pregnancy disorders, and those who gave birth to a neonate with a birth weight below the 10th percentile or with congenital or genetic abnormalities were excluded from the analysis as these factors may influence myocardial deformation values’.

I did not find any point where it is mentioned that clips were selected after the birth of baby. If this is so, please mention it otherwise remove this statement.

5) Under data acquisition, these lines seem accessary and should be removed ‘Adequate quality fetal heart clips can be achieved by an appropriate setting of the region of interest (ROI)8, and optimal settings of depth, width, and zoom box help to achieve maximum FR, while not critically degrading image quality minimizing the impact of potential speckle anisotropy on fetal 2D-STE.

Add objective points on which you checked image quality, via in a table or here in text.

6) Under angle of Insonation 2nd paragraph needs to be rephrased.

7) Results are not written in a very structured manner, please revise it.

My Best

Reviewer #2: The article is very well conceptualized. the authors have explained the process of speckle tracking frame rate and GLS which are actually not easy to understand in simplified way. They have already discussed their limitation in terms of retrospective data and unavailability of normal values, but articles with scientific content like these should be encouraged as these will set the trend for more work and normal standards. i must congratulate the authors on their extremely important and hard work.

**********

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Reviewer #1: Yes: Fatima Ali

Reviewer #2: Yes: Shazia Mohsin

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The impact of angles of insonation on left and right ventricular global longitudinal strain estimation in fetal speckle tracking echocardiography.

PONE-D-23-04326R1

Dear Dr. Thomas Johannes Nichting

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.

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Kind regards,

Zahra Hoodbhoy

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

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

**********

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

Reviewer #1: Yes

**********

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

**********

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

**********

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 study is very interesting and would be beneficial for readers to replicate. The objectives and methods were well defined. The study should not submit in other journal, which is against publication ethics.

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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: Fatima Ali

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