PONE-D-19-33576

Interpretable  brain age prediction using linear latent variable models of functional connectivity

PLOS ONE

Dear Dr Monti,

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Carlo Vittorio Cannistraci

Academic Editor

PLOS ONE

Additional Editor Comments (if provided):

Dear Authors

please address carefully all the comments advanced by the Reviewer

thanks

Carlo Vittorio Cannistraci

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Comments to the Author

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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

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

Reviewer #1: Yes

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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

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Reviewer #1: 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: The work proposed a very interesting a powerful analytical framework to study the aging dynamics of human functional connectivity. The mathematical presentation is flawless and clearly presented. Interestingly, the method appeared extendable to different contexts studying the dynamical aspects of functional connectivity, a relevant topic to date. First of all, authors should consider this aspect in the discussion/conclusion section. Moreover, Interested readers will find all details in order to reproduce results. However, I have some complains that authors should accomplish upon acceptance of the work:

1. Although authors use HCP Young Adult dataset just for test, they should declare the number of subject used.

2. Most importantly, within the human connectome project, there exists a similar collection called "HCP Aging"

chracterized by 1200 Subjects in the age range of 36-100+ years old. That's the dataset they should test.

3. If, the python "plot_glass_brain" function has been used to plot figures 5 and S4 (as I assumed), they should state it because otherwise it is necessary to specify the x-y-z coordinates. That function put in foreground every network

elements (nodes/edges) and the brain in background and it is particularly useful in displaying brain network.

4. However,

authors stated (in captions and text) those plots as "networks" but just nodes (ROI centroids?) are presented. This discrepancy should be fixed.

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Reviewer #1: Yes: Antonio Giuliano Zippo

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Interpretable  brain age prediction using linear latent variable models of functional connectivity

PONE-D-19-33576R1

Dear Dr. Monti,

We are pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it complies with all outstanding technical requirements.

Within one week, you will receive an e-mail containing information on the amendments required prior to publication. When all required modifications have been addressed, you will receive a formal acceptance letter and your manuscript will proceed to our production department and be scheduled for publication.

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With kind regards,

Carlo Vittorio Cannistraci

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: (No Response)

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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: Antonio Giuliano Zippo