Predictive Ability of Fahrenheit, a Hand Motion Recording System for Assessing Hand Motor Function in Patients with Hemiplegia Post-Cerebrovascular Disease—A Pilot Study
Round 1
Reviewer 1 Report
Warsaw 20.08.2021
To: Authors
Review of manuscript -Manuscript ID: applsci-1359138
The paper presents an interesting and important report that may become a determinant of the evaluation of the motor function of the distal part of the upper limb. The title encourages you to read the content of the article.
The summary is complete and meets the requirements.
The purpose of the publication was clearly defined.
The Method section presents some shortcomings.
First, a small group of patients was examined, patients with a fairly wide age range ("participants aged 20 and over 83"), having concurrent ischemic stroke and hemorrhage. It is good that the authors respond to some of them in study limitation and suggest further research. In connection with the above, the presented studies should not be called pilot? I propose to consider the above.
There are no criteria for inclusion in the research - please complete.
In my opinion, there is a lack of a more accurate assessment of the functional state of the collected group of people (muscle tension, mobility of the entire examined upper limb, evaluation of trunk stability); As the authors write, the patient is in a certain position during the examination = sitting and his upper limb is in a certain position, which for some reason they have adopted for the examination (neuralgia in the shoulder joint, flexion in the elbow joint, etc.). From the text and results of the presented research, I do not know why such an item for the study and whether the results would be different in a different item. The authors related their own research to the functional Brunnstrom study, perhaps they thought that the conditions for conducting their own research were to be the same as for Brunnstrom, and rightly so. Nevertheless, it is worth presenting patient studies in groups with different functional status and different starting positions for the study in the future.
The flow of participants in the study is also not clear (how many people started, how many were analyzed), and the authors describe relatively precisely how the results of observations were verified by physiotherapists and mention there that when the results were discrepant, the majority was chosen (how to choose the majority, when the three evaluators have a different rating) - incomprehensible. I propose to consider the patient flow diagram.
The results of the study confirm the assumptions of the work.
Discussion_ the authors wanting to emphasize the importance of the CeVD patient assessment model developed by them could devote more space to the study of muscle tension and strength as well as the motor assessment of the affected upper limb and trunk. After all, recovery of the distal function of the upper limb is not an isolated process. It is worth citing more literature. This would increase the number of references, of which there are relatively few in this study (22 items).
The main problem that reduces the importance of the presented research is the small group of patients and there is no precise assessment of the functional state of the gathered group of people.
Overall, the study aimed to present the developed model, Fahrenheit, which uses the LMC as a sensor to measure hand movements during recovery from motor palsy following CeVD according to the BRS criteria. In addition, the authors assessed whether Fahrenheit was able to predict the BRS score for the affected hand of patients after CeVD.
This study is important for the functional assessment of patients, especially since, as the authors themselves write, this type of study allows for the presentation of objective quantitative results. However, the research requires clarification and confirmation on a large, homogeneous group of participants.
The work requires corrections before it is allowed to be published.
Author Response
We greatly appreciate all comments and feedback from Reviewer #1.
Reviewer #1
To: Authors
Review of manuscript -Manuscript ID: applsci-1359138
The paper presents an interesting and important report that may become a determinant of the evaluation of the motor function of the distal part of the upper limb. The title encourages you to read the content of the article.
The summary is complete and meets the requirements.
The purpose of the publication was clearly defined.
The Method section presents some shortcomings.
Comment 1
First, a small group of patients was examined, patients with a fairly wide age range ("participants aged 20 and over 83"), having concurrent ischemic stroke and hemorrhage. It is good that the authors respond to some of them in study limitation and suggest further research. In connection with the above, the presented studies should not be called pilot? I propose to consider the above.
Response to Comment 1
Thank you for your comment. We agree with you; therefore, we have added "pilot study" to the title, abstract, and text as suggested.
Title: “Predictive Ability of Fahrenheit, a Hand Motion Recording System for Assessing Hand Motor Function in Patients with Hemiplegia Post-Cerebrovascular Disease-A Pilot study”
“Thirty-two inpatients with CeVD were recruited in this pilot study.” (page 1, line 20)
“The results of this pilot study suggest that Fahrenheit, a new method for assessing finger motor function, may be a valid method for evaluating prognosis and treatment efficacy in patients with hemiplegia following CeVD.” (page 10, lines 306-308)
Comment 2
There are no criteria for inclusion in the research - please complete.
Response to Comment 2
Thank you for the comment. The inclusion criterion has been added as follows: The eligibility criterion for this study was participants aged 20 or above who were recruited among all inpatients admitted at the Tokyo Dental College Ichikawa General Hospital between June 1, 2016, and March 31, 2021 who had suffered a stroke. (page 2, lines 84-87)
Comment 3
In my opinion, there is a lack of a more accurate assessment of the functional state of the collected group of people (muscle tension, mobility of the entire examined upper limb, evaluation of trunk stability); As the authors write, the patient is in a certain position during the examination = sitting and his upper limb is in a certain position, which for some reason they have adopted for the examination (neuralgia in the shoulder joint, flexion in the elbow joint, etc.). From the text and results of the presented research, I do not know why such an item for the study and whether the results would be different in a different item. The authors related their own research to the functional Brunnstrom study, perhaps they thought that the conditions for conducting their own research were to be the same as for Brunnstrom, and rightly so. Nevertheless, it is worth presenting patient studies in groups with different functional status and different starting positions for the study in the future.
Response to Comment 3
Thank you for your comment. It provided us with important suggestions. For clarity, we added an experimental limitation as follows:
“Regarding the hand movements of patients with stroke, the movements of the shoulders and elbow joints are small, the displacement of the trunk is large, and the exercise time is long [23]. In this study, since the hand movement involves multiple joints including the joints in the trunk, patients could maintain the sitting position, and their hand function was evaluated with the forearm fixed with the arm rest. This position was adopted because the patient's hand movement had to be detected from beneath the position with an infrared camera. Therefore, the patients were required to maintain the wrist joint in the air, and it cannot not be ruled out in this experiment that this continuous movement induced spastic contraction. If the movement of the patient's hand was affected by the position of the forearm and muscle tones of the other body, it is necessary to keep the wrist joint fixed and analyze the movement of fingers in a subsequent experiment.” (page 9, lines 295-304)
Comment 4
The flow of participants in the study is also not clear (how many people started, how many were analyzed), and the authors describe relatively precisely how the results of observations were verified by physiotherapists and mention there that when the results were discrepant, the majority was chosen (how to choose the majority, when the three evaluators have a different rating) - incomprehensible. I propose to consider the patient flow diagram.
Response to Comment 4
We agree with this comment and have added a figure on the patient flow diagram (Figure 3) and experimental procedures.
Comment 5
The results of the study confirm the assumptions of the work.
Response to Comment 5
We appreciate your comment on the results of our study.
Comment 6
Discussion_ the authors wanting to emphasize the importance of the CeVD patient assessment model developed by them could devote more space to the study of muscle tension and strength as well as the motor assessment of the affected upper limb and trunk. After all, recovery of the distal function of the upper limb is not an isolated process. It is worth citing more literature. This would increase the number of references, of which there are relatively few in this study (22 items).
Response to Comment 6
Thank you for your comment. We agree that finger paralysis involves multiple joints of the upper limbs and trunk, and factors such as muscle tone and strength are important in the evaluation model; however, we did not collect these data. Therefore, the questions in this treatise cannot be answered even with the addition of several references. This issue has been described in the study limitations. Please see page 9, lines 295-304.
Comment 7
The main problem that reduces the importance of the presented research is the small group of patients and there is no precise assessment of the functional state of the gathered group of people.
Response to Comment 7
In this study, the patients were recruited in the acute phase and were not allowed to perform detailed muscle strength and tone examinations to ensure physical safety. Therefore, our data did not contain necessary information indicated in the comment. This has been explained in the limitation of the research as follows:
“In this study, we could not collect data on the muscle strength, tone, and somatosensory function that affect finger paralysis. Since the patients in this study were recruited in the acute phase, the experimental period was limited, and it was not possible to measure the muscle strength. With these detailed data, the prediction of finger paralysis would have been more accurate.” (page 9, lines 285-294)
Comment 8
Overall, the study aimed to present the developed model, Fahrenheit, which uses the LMC as a sensor to measure hand movements during recovery from motor palsy following CeVD according to the BRS criteria. In addition, the authors assessed whether Fahrenheit was able to predict the BRS score for the affected hand of patients after CeVD.
This study is important for the functional assessment of patients, especially since, as the authors themselves write, this type of study allows for the presentation of objective quantitative results. However, the research requires clarification and confirmation on a large, homogeneous group of participants.
Response to Comment 8
Thank you for the depth of knowledge of this study. We have added this information in Discussion section as follows:
“To comprehensively evaluate Fahrenheit and reduce the likelihood of type 2 errors in future studies, it is necessary to repeat this study with a larger sample size; homogeneous group of participants, where data from mild to severe will be obtained; and researchers ensuring that patients comply with the described process and methods.” (page 9, lines 291-294)
Comment 9
The work requires corrections before it is allowed to be published.
Response to Comment 9
We agree with this comment. The manuscript has been revised in accordance with the suggestions provide above.
Reviewer 2 Report
Saito and colleagues investigated whether their newly developed kinematic analysis system (Fahrenheit) could predict the outcome of the Brunnstrom recovery stage (BRS) assessment in individuals with hemiplegia. From their investigation, they conclude that Fahrenheit has high predictability of the BRS assessment criteria. The manuscript is very clearly written and the results are useful. I have two comments/questions with regards to the manuscript, but the authors have done a great job.
First, I would like to see a bit more detail added about the t-tests in the Statistical Analysis section, for instance, what type of t-tests and how the very different sample sizes were handled.
Second, the authors state in the limitations section that they were likely underpowered based on their sample size calculation. I'm wondering then what the rationale for not collecting more patients to be appropriately powered was.
Author Response
Your comments have greatly encouraged us.
Reviewer #2
Saito and colleagues investigated whether their newly developed kinematic analysis system (Fahrenheit) could predict the outcome of the Brunnstrom recovery stage (BRS) assessment in individuals with hemiplegia. From their investigation, they conclude that Fahrenheit has high predictability of the BRS assessment criteria. The manuscript is very clearly written and the results are useful. I have two comments/questions with regards to the manuscript, but the authors have done a great job.
Comment 1
First, I would like to see a bit more detail added about the t-tests in the Statistical Analysis section, for instance, what type of t-tests and how the very different sample sizes were handled.
Response to Comment 1
We appreciate reviewer #2 for the understanding and interpretation of the results of this manuscript. We improved the manuscript by including the following sentence in the Methods section:
“Continuous data is presented as mean values ± SD. The mean values ± SD recorded with Fahrenheit (BRS score was assigned as 0/1) were compared between participants who obtained a BRS score of 1 (well-accomplished movement) and those who obtained a BRS score of 0 (insufficient movement) using an unpaired t-test to determine if they were significantly different.“ (page 5, lines 155-158)
Comment 2
Second, the authors state in the limitations section that they were likely underpowered based on their sample size calculation. I'm wondering then what the rationale for not collecting more patients to be appropriately powered was.
Response to Comment 2
One of the reasons for not recruiting a sample size that could improve the power of this study was that majority of the patients at the stroke center of the acute care hospital had savior disorders and impaired consciousness. In addition, the number of rehabilitation staff was small compared to the number of hospitalized patients, and it was extremely difficult to perform the experiments during the treatment period. Since the institution used in this study is a university hospital and most of the patient stay for a short duration in the hospital, it was difficult to recruit the total number of participant required for minimum analysis. This explanation has been added to the Discussion as a limitation.
We appreciate all the comments and suggestion provided to improve our manuscript.
