PONE-D-22-00890Development of a gait speed estimation model for healthy older adults using a single inertial measurement unitPLOS ONE

Dear Dr. Kim,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

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Yaodong Gu

Academic Editor

PLOS ONE

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Additional Editor Comments (if provided):

Discussion part shall be more detail to describe the gait analysis methods.

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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: This manuscript entitled “Development of a gait speed estimation model for healthy older adults using a single inertial measurement unit” primarily aimed to develop an algorithm for estimating the gait speed of healthy older adults using data captured by an inertial measurement unit placed at the center of body mass. To enhance the quality of the manuscript, revise suggestions are given below.

At the beginning of the whole study, the author needs to present your work as less word as you can, which include purpose, methods, results and conclusion. During the abstract part, it cannot catch the redear attention at the first time. Please rewrite this part.

Please further prove why this study is important. We have to confirm that this research is meaningful, rather than there is no such study that has been done yet. Author needs to well-introduce what kind of problems or issues would be solved after this research.

Please make your methods part more specific with some test images, and make your method more specific as well. This short explanation cannot easily understand.

Did the author perform Shapiro-Wilk normality tests?

Reviewer #2: This paper developed an algorithm for estimating the gait speed of healthy older adults using data captured by an inertial measurement unit (IMU) placed at the center of body mass (CoM). The model exhibited excellent accuracy in estimating the gait speed measured by the GAITRite. This quantitative gait evaluation method is completely derived from the information of IMUs. This technology has vast implications for gait estimation if properly validated. The work is interesting, however, there are a few changes that could be made to make the results more accessible and clear to readers, in details:

1.The abstract is not clear. The significance and challenges should be presented in the abstract.

2. The motivations should be strengthened when revising in the introduction. The authors should further enlarge Introduction with current results to improve the research background.

3. What are the limitations of the proposed gait estimation method? The author did not mention it in the paper.

4. It would be nice to discuss the following papers in the paper:

- Zhang, M., Wang, Q., Liu, D., Zhao, B., Tang, J., & Sun, J. Real-time gait phase recognition based on time domain features of multi-MEMS inertial sensors. IEEE Transactions on Instrumentation and Measurement, 2021,70, 1-12.

- Marta, G., Alessandra, P., Simona, F., Andrea, C., Dario, B., Stefano, S., Stefano, M.. Wearable Biofeedback Suit to Promote and Monitor Aquatic Exercises: A Feasibility Study. IEEE Transactions on Instrumentation and Measurement, 2020, 69(4), 1219-1231.

- S. Qiu, H. Zhao, N. Jiang, D. Wu, G. Song, H. Zhao, Z. Wang. Sensor network oriented human motion capture via wearable intelligent system, International Journal of Intelligent Systems, 2022, 37(2): 1646-1673.

5.Transitions from section to section should be smoother

6. What are the implications of the findings? More discussion should be provided in the manuscript. The factors that influence the accuracy of gait estimation should be analyzed in more detail in the discussion section.

7. How do you deal with inertial sensor misplacement?

8. Some individuals are not willing to wear additional sensors on their body, what is the potential of smartphone serving as the data collection tool?

9.Proofread the paper and improve readability.

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Reviewer #1: No

Reviewer #2: No

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Development of a gait speed estimation model for healthy older adults using a single inertial measurement unit

PONE-D-22-00890R1

Dear Dr. Kim,

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,

Yaodong Gu

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

N/A

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: (No Response)

Reviewer #2: 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: (No Response)

Reviewer #2: Yes

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

Reviewer #1: (No Response)

Reviewer #2: Yes

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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: (No Response)

Reviewer #2: Yes

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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: (No Response)

Reviewer #2: Yes

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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)

Reviewer #2: This paper proposed a model for accurately estimating the gait speed of healthy older adults using the data captured by an inertia sensor placed at their center of body mass (CoM). I value the authors efforts to answer all the previous concerns and feel that the paper overall improved. It seems to me that most of the previous concerns were well addressed in the revised manuscript. Overall, the revised paper quality largely meets the requirements of "PLOS ONE", hence the manuscript could be accepted for publication.

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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: No

Reviewer #2: No

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