The Latest Progress and Development Trend in the Research of Ballistocardiography (BCG) and Seismocardiogram (SCG) in the Field of Health Care

Round 1

Reviewer 1 Report

This study describes a bibliometric analysis method to review the existing documents published in the past 20 years on ballistocardiography (BCG) and seismocardiogram (SCG). The BCG phenomenon was first observed in 1877, and the SCG was first observed in 1961, so these methods are actually much older than 20 years. These methodologies were almost forgotten, mostly because of the intricate setup of equipment that is needed for the measurements, as well as due to the fact that easier and more elegant methodologies have become available for cardiac diagnoses, such as the electrocardiogram (ECG). However, in the light of new technological developments, such as newly developed small sensors, these methodologies are gaining new interest. 

Still, both methods are  with a number of sometimes problematic issues, such as lack of biological meaning and clinical relevance, lack of standardization and reference values, effect of respiration, posture, sensor adherence (to name a few). 

As an overall review article on the BCG and SCG methods, the 2014 article by Omer Inan et al (see refs 6 and 8 in this article) gives more in-depth information and background. The only new and interesting information here are displayed in figure 6 (distribution in interest per country) and figure 7 (classification of published articles on BCG and SCG). Question is whether this is enough to make the manuscript interesting enough.

Some minor comments:

• English language and wording could be improved
  • line 38-39: 'back to the stage of history'??
  • line 66-68: strangely and incorrectly formulated
  • line 305-306: meaning what?
• Figure 5 is irrelevant
• Reference list:
  • reference 6 and 8 are the same (I have not checked all references)
  • non-english references should be avoided (e.g.: ref 81)

Author Response

Following your most valuable suggestions, we have revised the paper.

• Additional descriptions of applications of BCG/SCG for Figure 3 (fig. 4 for the last version) were introduced.
• Figure 1. We cited a ECG/BCG/SCG combined illustration and descriptive text were changed respectively.

Limitations of BCG/SCG are explained in chapter 4.3.

3,4,10) As you have pointed, we did a search of more references and added descriptions concerning the methodological limitations of BCG and SCG in 4.3.

Problematic english phrasing was solved by consulting experts in this domain.

The issue of repeated references was mended, we checked the whole reference list for duplicates and non-english refs was excluded from the list.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments on the review paper entitled “The Latest Progress and Development Trend in the Research of Ballistocardiography (BCG) and Seismocardiogram (SCG) in the Field of Health Care” by Xiuping Han et al. (applsci-1316257)

A review paper related to the research of BCG and SCG has already been published in 2015 [1]. It seems that present review paper specializes in healthcare applications and in the information after 2015. Therefore, we could see the difference from the previous paper. However, it is not suitable for publication in Applied Sciences in its present form due to the following reasons.

1. Several measurement devices are introduced in Fig. 4, however, the description of them are not sufficient. The authors should state how to measure BCG and SCG in more clearly.
2. The standard waveforms of BCG and SCG are depicted in Figs. 1 and 3, respectively. However, I think they should be dipicted together with an ECG waveform, since time history of those waveforms should be related.
3. The authors states that there are several obstacles for the promotion of practical use. They should describe those obstacles more clearly.
4. I think most of the systems are non-contact (non-invasive) measurement. Therefore, there should be several noises as well as human motion artifact. Even in the ECG measurement, they have been the serious problems. Please describe the research and advancement in those issues.
5. Figures 7 and 10 are not clear (Characters are too small). The have to be improved.
6. Table 2: The caption should be “Typical Research of Application of BCG/SCG in Clinic Medicine in the Tears 2015-2020.
7. Refelences 81-102 are not listed.
8. Sections 3.3.1 and 3.3.3 are the same title. Please check. Also there is no 3.3.2
9. Chinese characters are mixed. (lines 125-126 and Ref. 81). Please check it.

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[1] Omer T. Inan et al., IEEE Journal of Biomedical and Health Informatics 19, 4, 1414 (2015).

Comments for author File: Comments.docx

Author Response

Following your most valuable suggestions, we have revised the paper.

• Additional descriptions of applications of BCG/SCG for Figure 3 (fig. 4 for the last version) were introduced.
• Figure 1. We cited a ECG/BCG/SCG combined illustration and descriptive text were changed respectively.

Limitations of BCG/SCG are explained in chapter 4.3.

3,4,10) As you have pointed, we did a search of more references and added descriptions concerning the methodological limitations of BCG and SCG in 4.3.

Problematic english phrasing was solved by consulting experts in this domain.

The issue of repeated references was mended, we checked the whole reference list for duplicates and non-english refs was excluded from the list.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

The authors have added additional information to the manuscript to make it more comprehensible. But still, as the authors write themselves in the manuscript, the problem with both methodologies is the subjectivity and difficulty to standardize the results. What would be needed is clear explanation of which variables can be measured accurately and satisfactorily with these methods.

Lines 392-395: (Final conclusion): this is the first time "artificial intelligence" is mentioned; therefore there is no proof (in this manuscript) that this will play a role. Furthermore: on which grounds do the authors base their conclusion that "the medical and health products based on BCG / SCG technology will gradually enter the market" and that " (it) is expected to find wider and wider use." ?

 

Furthermore, there are still many parts in the manuscript where the authors write statements that are really hard or impossible to understand:

Lines 273-274: What is meant with: "shows that BCG / SCG technology took a high proportion in the medical field, up to 79.78 %," ??

Line 280: "BCG / SCG technology research is becoming more micro, deep and comprehensive." What is meant here??

Lines 288-290: "Such a diagnosis has a micro-nature, with the advantages of strong orientation of data collection and analysis, in-depth signal interpretation, detailed diagnosis results and high 289 medical reference value." I have really no clue what the authors mean to say here. 

Lines 349-352: "Amirtahà Taebi et al. [104] also suggested constructive 349 proposition including building a computational model based realistic computational 350 simulation to predict the effects of different variables and setting a comprehensive library 351 of SCG signals facilitating works of researchers interested in SCG." I don't have a clue what the authors are saying here.

Lines 398-390: "and timely nursing intervention for the early detection of diseases and the degree of progression be conducted in care in the home environment." I would leave this out: you are trying to say 3 different things in one sentence.

 

Minor comments:

line 332: "Inan Omer et al. [6,8]," -> Only ref 6 is by Inan. By the way: leave out "Omer" here, it is his first name.

textual:

line 207: leave out 'etc'
line 215: 'golden law'-> 'golden standard'
Line 381: "abroad"  -> "broad"

 

Author Response

We have read and taken your comments and suggestions on our manuscript.

Firstly, an explanation on the correlation between BCG signal features and cardiac activities was added in the part Subjectivity and objectivity.

In the conclusion, we deleted the “artificial intelligence” part since it was neither well introduced nor the content that this article focused on. The last sentence about the expectation of BCG/SCG is rephrased based on their experimental applications mentioned 1.3. revival of BCG/SCG.

We also looked into some langue problems and reformulated those sentences.

Lines273-274 -> deleted

Line 280 -> deleted

Lines 288-290 -> “Diagnoses based on BCG/SCG measurements mentioned previously has methodological privilege on data analysis and signal exploration giving a valuable result for medical reference.”

Lines 349-352 -> “Amirtahà Taebi et al. [104] proposed to make a comprehensive  SCG signal database which will play an important role in stimulating basic research and medical device development.”

Line 398-390 -> “Only by commercializing BCG / SCG technology products, those difficulties in technical implementation process could be overcome..”

Line 332 -> "Inan et al. [6],"

line 207 -> leave out 'etc'

line 215 -> 'golden standard'

Line 381 -> "broad"

Reviewer 2 Report

The manuscript has been improved. The authors have addressed the concerns which I have stated. I think this manuscript will be acceptable as a review paper in Applied Sciences, since the content specializes in healthcare applications and up-to-date (after 2015) information compared to the previous review paper.

Author Response

Thanks for reviewing our paper. Your precious advice helps us a lot!

Round 3

Reviewer 1 Report

First, I wish to congratulate the authors on all the work they have done to read and discuss all  referenced articles on BCG and SCG. I think the present form of the manuscript is a useful recapitulation of all these articles, and is useful for people who want to get involved in further research in BCG and/or SCG. 

The authors have taken all my comments from the first and second review into account, almost all satisfactorily.

I still have 2 comments, but I trust that the authors can amend these without the need for a 3rd review on my site.

First comment: the last sentence in the new paragraph in lines 272-278: "This indicates that in the application of sleep health management, cardiovascular monitoring and diagnosis, and respiratory testing, etc. are the directions of future development.", this sentence should be rephrased. The authors probably mean to say that "the directions of future development of BCG and SCG are the application of sleep health management, cardiovascular monitoring and diagnosis, and respiratory testing".

Second comment: the sentence now in lines 288-290 is still incomprehensible for me: “Diagnoses based on BCG/SCG measurements mentioned previously has methodological privilege on data analysis and signal exploration giving a valuable result for medical reference.”. Please rephrase this sentence to make clear what you mean.

Author Response

We have made some corrections in the line you point out. Thanks for reviewing our paper, your precious advice gives us the way to improve our paper.