The Effect of Hearing Aid Amplification on Gait Parameters: A Pilot Study Using Ear-Worn Motion Sensors

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Dear Authors, Thank you for the opportunity to review an innovative and excellent study. There are many merits and some points for strengthening to assure all readers can find the impact of the studies.

The key question for the authors to consider is to assure that the validity of the method is made clear and presented as early as possible. The reader has the first opportunity to question the impact of ear vs foot worn IMU data in 3.3, and currently continues to read with the question in mind until figure 4 (after finding 4.3 and 5.1). At this point the reader sees fig 4 a and b and is looking for confirmation of significance testing to confirm that the visible differences could impact all the other results or indeed can be closed and discarded from clouding any interpretation of the remaining findings. Consequently IF there any significances found for figure 4 a and b that all remaining commentary especially when noting differences to the literature (301-2) should be revised. Without this question answered the reader is left to think that the lack of effects being presented are precisely because of the differences in fig 4 a and b. Hopefully this information can be made either more obvious to a new reader or a few comments in the right place are all that are needed, either way please help the reader answer this doubt as early as possible.

Other considerations are:

Line 28-30 – a reference for evidence should be provided

Figure 1 – The style and simplicity of the figure is excellent. Logically, I would expect to only see the Amplification as On / Off – weren’t the Gait Parameter (GP) analysis and Accelerometer (Acc?) on in all cases to capture the differences in all scenarios? Why would the accelerometer and GP analysis be off for any part? The Data collection section does not indicate otherwise

Line 157 – section rather than chapter

Line 168-9 – “detection algorithm from [20].” Was an intext citation missing here? Should this say ‘detection algorithm from Seifer et al [20]’? Similar issue for line 170 for [21]

Why is figure 4 not provided in the results? Also Table 3 and 4 should be in the results sections?

4.2 effects on gait line 242 note that step length  and gait velocity were significantly lower, these were the 2 out of 3 estimations with the greatest variance from ear vs foot – what impact does this have? What results are generated using foot data vs ear data for gait line?

Table A2 – please consider using ^ or *, bold is not very clear to all readers across media types.

Why is table A2 in the middle of the references?

Author Response

Dear Reviewer, 

We would like to sincerely thank the reviewer for the kind and constructive comments, as well as the positive evaluation of our study. We greatly appreciate your suggestions, which helped us to further strengthen our manuscript. In the revised version, we have addressed each of your comments and incorporated the respective changes to improve clarity, validity, and presentation. Please find our detailed responses below as PDF, with all changes highlighted in red in the updated manuscript.

Best regards, 
The Authors

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The authors in their article wanted to evaluate the effects of acoustic amplification provided by hearing aids on gait parameters in individuals who had never tried hearing aids. The methodology is clear and well represented, the English is well understandable. The topic in my opinion is of particular interest. Only for improvement purposes, I suggest making some small changes before publication.

The abstract should be structured (Background/Objectives, Methods, Results, Conclusions).
 
Had the participants never used hearing aids before? I suggest specifying this.
 
Table 1, correct PTA with PTA4.
 
Discuss the fact that patients with greater hearing loss could make a greater effort and therefore have worse gait parameters. The patients in the study had a PTA of 39.9 ± 11.3, so the results obtained could be due to this. Discuss these aspects.
 
The hearing aid, the coupling systems used, but also the natural resonance of the ear canal, can determine an insertion gain different from that prescribed and estimated by the fitting software. The authors did not verify this with real ear measurements. Since effective and adequate acoustic amplification is a determining factor in this study, it is necessary to reiterate this aspect.
See and cite
Alberti G, Portelli D, Loteta S, Galletti C, D'Angelo M, Ciodaro F. Open-fitting hearing aids: a comparative analysis between open behind-the-ear and open completely-in-the-canal instant-fit devices. Eur Arch Otorhinolaryngol. 2024 Nov;281(11):6009-6019. doi: 10.1007/s00405-024-08836-1
 
I suggest the authors make a brief mention in the discussion commenting on the results obtained with those of the gait assessment in patients with cochlear implants
See and cite
Murray D, Viani L, Garvan J, Murphy A, Vance R, Simoes-Franklin C, Smith J, Meldrum D. Balance, gait and dizziness in adult cochlear implant users: A cross-sectional study. Cochlear Implants Int. 2020 Jan;21(1):46-52. doi: 10.1080/14670100.2019.1662978.
 
Kaczmarczyk K, Błażkiewicz M, Wiszomirska I, Pietrasik K, Zdrodowska A, Wit A, Barton G, Skarżyński H. Assessing Gait Stability before and after Cochlear Implantation. Biomed Res Int. 2019 Jan 14;2019:2474273. doi: 10.1155/2019/2474273
 
As for future prospects, these sensors as well as acoustic stimulation, could have a clinical utility especially in the forms of Meniere's Syndrome where the hearing loss has now settled but there are still balance disorders. Having a system that monitors gait over time could be useful.

Author Response

Dear Reviewer, 

We would like to sincerely thank the reviewer for the thoughtful and encouraging feedback, as well as the constructive suggestions for improvement. We are pleased that you found the methodology well represented and the topic of high interest. We have carefully addressed each of your comments to further enhance the clarity and quality of the manuscript. Please find our detailed responses below as PDF. All corresponding changes have been highlighted in red in the revised manuscript.

Best regards, 
The Authors

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The abstract presents an interesting study that applies signal processing techniques to investigate the impact of hearing aids on gait performance. The integration of an accelerometer within the hearing aid and the application of the EarGait framework represent innovative approaches in this domain.
1) The sample size is set to 25, which is relatively small for biomedical research. In related studies, the sample size is a critical factor that can significantly influence the generalizability of the results. A larger sample size would provide more statistical power to detect meaningful changes in gait performance and improve the robustness of the findings. It is important to provide a rationale for the chosen sample size, such as power analysis or feasibility considerations, to justify its adequacy for the study objectives.
2) Given that repeated measurements have been conducted, selecting an appropriate significance level (SL) is crucial to mitigate the risk of Type I errors (false positives) arising from multiple comparisons. However, the manuscript lacks a description of how the SL was adjusted to account for these repeated measurements.
3) While the manuscript highlights the high accuracy of the ear-worn gait analysis system as validated against foot-worn sensors, further validation against a gold standard, such as motion capture systems, in addition to foot-worn sensors, would significantly enhance the credibility of the findings.

Author Response

Dear Reviewer, 

We would like to sincerely thank the reviewer for the constructive and thoughtful feedback, as well as the recognition of the innovative aspects of our study. We greatly appreciate your comments, which have helped us to refine and clarify important elements of the manuscript. In the revised version, we have carefully addressed each of your suggestions and made corresponding improvements. All changes are highlighted in red in the updated manuscript. Please find our detailed responses in the PDF below.

Best regards, 
The Authors

Author Response File: Author Response.pdf

Round 2

Reviewer 3 Report

Comments and Suggestions for Authors

All concerns have been addressed.