Heart Rate Variability during Virtual Reality Activity in Individuals after Hospitalization for COVID-19: A Cross-Sectional Control Study

Round 1

Reviewer 1 Report

Dear authors, thanks for the opportunity to review this paper.

The topic is interesting and also applicable in clinical settings. However, some issues have to be revised.

-         Abstract. The abstract needs to be more precise and better presented. The study's methodology needs to be clearly described, and the results could be more precise. Furthermore, in general also, for the conclusions, the implications for practice do not emerge, which should be the most important thing to describe.

-         Background. The introduction is oriented towards describing cardiological problems rather than previous efficacy studies on virtual reality in the cardiological field. The article would benefit from highlighting the innovative elements on the subject and the importance of using virtual reality.

-         Methods. This section should be implemented. It is necessary to broaden the inclusion and exclusion criteria of the study and the specific selected characteristics. Furthermore, some emerged variables in the results (e.g. Table 1 – hospitalization for covid or habits) are not clearly described in the methods and are pre-specified in the study. It is necessary to extend the methodology and organize it. Moreover, it is not clear why results were organized in age classes.

-         Results. The statistical analysis conducted is pervasive in their description. Table 1 is not presented because some variables are not optimally described: patients presenting PA could be related to habits? What is the hospitalization for covid? What exactly does it mean?

-         Discussion. The discussions are very well-detailed towards a clinical description. A broader description of other experiences with virtual reality applied to cardiology and the use that this could have in a practical context needs to be included.

 

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

The authors investigate whether the practice of a task using a VR activity will positively influence physiological variables and how the performance of physiological variables will be in post-hospitalization patients for Covid-19. The idea of the paper is interesting and it is well writen, with a few minor errors found. Some points should be clarified in order to improve paper quality and reader's understanding.

 

Despite having VR in the title of the paper, it seems to me that VR has a secondary role in this work. Since the activity that must be performed by patients in VR involves body movements, the protocol could apply a different activity to the patients including body movement, but not VR. Please explain/justify why is VR necessary in this work. This should be clear in the introduction of the work.

 

Another important point to be addressed is the findings of the work. According to the end of the abstract and also the Conclusions section, "Conclusion: COVID-19 affects the ANS system of older patients’ post-hospitalization and the higher RPE in COVID-19 patients reflect altered physiological and autonomic responses." Previous works already concluded that Covid-19 affects the ANS system of patients, such as "Alteration of Autonomic Nervous System Is Associated With Severity and Outcomes in Patients With COVID-19", so what is the novelty in this case? Please make this clear in the paper.

 

In the Conclusions section, the authors say that "Additional assessments at different times could bring important information about the effects of physical activity in this period." What do you expect to find by assessing the post-covid patients at different times?

 

Please make clear the importance of virtual reality in this study. Also, please show that the conclusions of the paper bring some novelty so that the paper can be accepted for publication.

 

General comments and minor errors found are listed as follows.

 

"the practicing a task" -> "practicing a task"

" moves their arms" -> " moves his/her arms"

figure 1 is not mentioned in the text

"The participants of both groups signed the free and informed consent form, were aged from 18 to 90 years" -> the participants were divided into three groups, "25-40 years, 41-60 years, and 61-80", were the patients with more than 80 years excluded?

"discussed below:" -> "discussed below."

some terms are defined more than once in the text. example: HRV

"games demonstrate" -> "games, demonstrate"

" activities, do" -> " activities do"

"patients post-Covid However," -> "post-Covid patients. However,"

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

I'm satisfied with the modifications and responses from the authors. I believe the paper can be accepted in its current form. Congratulations!