User Experience in Immersive Virtual Reality-Induced Hypoalgesia in Adults and Children Suffering from Pain Conditions

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The comments and suggestions for the authors are listed in the file attachment.

Comments for author File: Comments.pdf

Author Response

"Please see the attachment file with the responses to the reviewers"

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The manuscript provides a comprehensive literature review, covering a broad spectrum of studies from experimentally induced pain to clinical studies involving both acute and chronic pain in adults and children. This extensive inclusion demonstrates a thorough understanding of the field. The structured methodology, employing PICOT criteria for study selection, ensures a systematic approach and thorough documentation of the search strategy across multiple databases with relevant MeSH terms and keywords. 

The detailed analysis of various user experience (UX) factors such as distraction, presence, interactivity, gamification, and virtual embodiment is a significant strength. This in-depth exploration elucidates the mechanisms through which immersive VR can influence pain perception. Additionally, the discussion on potential hierarchical relationships between different UX factors and their cumulative effects on hypoalgesia offers a valuable perspective, which is essential for designing more effective VR-based pain management interventions. The manuscript also considers pediatric populations, emphasizing the differences in VR experience and effectiveness between adults and children. This focus is crucial as it highlights the necessity for age-appropriate VR content and hardware design. Moreover, the clear and logical organization of the manuscript, with distinct sections that build upon each other, contributes to its readability and coherence.

However, the discussion on adverse effects of immersive VR is limited, lacking detailed information on the nature and prevalence of these effects. A more comprehensive discussion would provide a balanced view of VR's use in pain management. The high variability in study designs, clinical pain profiles, and VR interventions among the included studies poses another challenge. This heterogeneity complicates the drawing of generalized conclusions. A more focused analysis on specific types of pain or VR interventions could yield clearer insights.

Furthermore, the review primarily relies on qualitative descriptions of study outcomes. The inclusion of more quantitative data, such as effect sizes and statistical significance of the hypoalgesic effects, would strengthen the conclusions. The manuscript also focuses more on the immediate hypoalgesic effects of VR, with insufficient exploration of the long-term effects and sustainability of pain relief provided by VR interventions. 

The review highlights that many studies do not report UX factors in detail, indicating a gap in the literature. This also suggests that the review may be limited by the quality of reporting in the primary studies. While the manuscript identifies gaps in the literature, it could offer more concrete recommendations for future research. Specific suggestions on study designs, populations, and types of VR interventions that should be explored would enhance its contribution to the field.

In conclusion, the manuscript provides a thorough and insightful review of the role of immersive VR in pain management, emphasizing the importance of various UX factors. However, it would benefit from a more balanced discussion on adverse effects, the inclusion of quantitative data, and a detailed exploration of long-term outcomes. Addressing these weaknesses in future revisions would significantly enhance the manuscript's impact on the field of digital health and pain management.

Author Response

"Please see the attachment."

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

User experience in Immersive Virtual Reality-induced hypoalgesia in adults and children suffering from pain conditions

Pain is the most common reason for medical consultation and use of health care resources. The high socio-economic burden of pain justifies seeking an appropriate therapeutic strategy. Immersive virtual reality (VR) has emerged as a first-line non-pharmacological option for pain management. However, the growing literature has not been accompanied by substantial progress in understanding how VR could reduce the pain experience, with some user experience factors being associated with the hypoalgesic effects of immersive VR. The aim of this review is: (i) to summarize the state of the art on the effects of VR on adults and children suffering from pain conditions; (ii) to identify and summarize mechanisms across immersive VR user experience influences hypoalgesic effects in patients with acute and chronic pain in adults and children. A critical narrative review based on PICOT-criteria was conducted that includes experimental studies or systematic reviews involving studies in experimental induced pain, acute pain or chronic pain in adults and children.  The results suggest an association between immersive VR-induced hypoalgesia and user experience such as distraction, presence, interactivity, gamification and virtual embodiment. These findings suggest that hierarchical relationships might exist between user experience-related factors and  greater hypoalgesic effects following an immersive VR intervention. This relationship needs to be considered in the design and development of VR-based strategies for pain management.

 

This study is very interesting regarding chronic pain and the potential of VR technology. The methodology followed is generally sound. However, I have two serious objections that need clarification

Lines 115-118

1.     The authors concluded by summarizing mechanisms across immersive VR user experiences that influence hypoalgesic effects in patients with acute and chronic pain in adults and children. They chose, based on a review of the literature, to focus on factors such as Distraction, Presence, Interactivity, Gamification, and Virtual Embodiment? Or did they conclude this based on their own meta-analysis?

2.     Lines 160-166. It is not clear to me why other underlying effects or factors were excluded from the analysis as presented in the relevant literature: like motivation to be involved in a new experience, the involvement in a new innovation, the enjoyment from the experience, or the increased effort that comes from a new experience.

Author Response

"Please see the attachment."

Author Response File: Author Response.pdf

Reviewer 4 Report

Comments and Suggestions for Authors

Comments to the Authors:

 

Dear authors, first I would like to express my gratitude for the opportunity to review your article. After a thorough analysis of the manuscript, I would like to provide some constructive suggestions to enhance the clarity and impact of your work:

 

 

1.Introduction

 

Reviewer: The introduction is well-conducted, however the authors need to clearly state which gap in the literature motivates the study, i.e. explain with previous literature which existing gap justifies this new research. In addition, the authors should reinforce the research objectives. On the other hand, when the authors state that: “According to this, depending on the intensity and quality of the experience generated by the virtual environment, as well as the type of device used according to the degree of immersion and stimulation of the sensory systems, the different modalities within the continuum of extended reality can be differentiated.” They should reinforce their knowledge of the application of this type of immersive equipment, and even refer to studies that have already applied it in other contexts, so that the reader also realizes that this type of strategy is already widespread and that it generates not only the participants' intention to use it, but also satisfaction. A quick search of the main academic databases reveals several studies that reinforce user intention after immersive experiences.

 

 

1.1.  Immersive Virtual Reality in the Approach to Pain

 

Reviewer: “However, some barriers to its implementation have also been reported, such as adverse effects, lack of knowledge about the technology, limitation in exposure times or the hygiene of the device.” The authors need to include the studies that identified these barriers.

 

 

Reviewer: “Therefore, better reported studies on these parameters are required to provide greater strength to the available evidence on the use of immersive VR in people suffering from pain conditions.” What studies have concluded this, the authors themselves? it is important to clearly identify this need.

 

 

Reviewer: “The decrease of pain reported by most patients suffering from pain after being exposed to a VR environment is what we refer to as "Immersive Virtual Reality-induced hypoalgesia".” What study or studies have concluded this?

 

 

Reviewer: “In the past few years, there has been significant advancement on effectiveness and hypoalgesic outcomes of VR technology in both acute and chronic pain.” Which study or studies report this advance? Which population is being considered?

 

 

Reviewer: “Different studies have shown that the quality of the experience delivered with VR, where the level of immersion, presence, and interactivity directly correlates with the magnitude of the hypoalgesic effect compared to non-immersive VR. Nevertheless, studies conducted to explore the hypoalgesic effects of immersive VR have given little attention to experience-related factors and have been largely under-reported. Similarly, few studies have explored the relationship between the magnitude of hypoalgesia effects, the clinical profile, and user experience factors. As noted, research to understand the mechanisms behind immersive VR has mostly been conducted with adults who have been experimentally pain-induced. The transferability of these findings to clinical scenarios or to people suffering from chronic pain has been required. For instance, several of these factors have been included under the umbrella term of VR, representing a real challenge to understand the specific characteristics of the interventions such as the magnitude of the effect of each of them. Hence, the relationship between user experience factors and hypoalgesic effects of immersive VR in people suffering from pain conditions is still unclear. Translating these scenarios to children with acute or chronic pain can become even more complex. All these components vary significantly more when the patient is a child.” Which studies are we talking about? How many studies? Which factors? Authors cannot refer to this type of information based solely on their own convictions. It is necessary to mention which studies confirm or suggest such considerations.

 

 

2.      Materials and Methods

 

Reviewer: “This is a critical narrative review which aims to address and understand the above specified question.” The authors should once again clarify what they are aiming for in this study and explain why they chose this methodological approach, mentioning that previous studies suggest this approach. On the other hand, the search process should be better explained, why PICOT-criteria and which ones. Also, why did the authors not consider the Scopus database? Why did they exclude non-immersive virtual reality? What are non-immersive VR experiences for the authors? VR360º? There are several clinical studies that successfully use VR 360º. Why did they exclude case studies, qualitative studies, book chapters?

 

 

4. Discussion

 

Reviewer: The discussion is well-conducted by the authors, however, given that the study generated many results, it would be important for the authors to add a new section dedicated to the theoretical and practical implications of the study, to condense the scientific contribution of the study and clearly state its importance in practical terms for the industry.

 

5. Conclusions

 

Reviewer: At this point, the authors should also mention which of the gaps in the literature were answered with this study, and which of the initially proposed objectives were achieved. They should also describe the limitations of the study and mention future lines of research based on the results obtained.

Comments on the Quality of English Language

English language just needs a minor revision.

Author Response

"Please see the attachment." 

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The authors have revised the manuscript according to some suggestions as attached file in the review report 1. However, the last suggestion hasn’t been included in the revised manuscript. Therefore, I recommend improving the manuscript as the comment in the attached file. 

Comments for author File: Comments.pdf

Author Response

Comment 1: Therefore, I suggest completing the introduction by citing some references as follows: Photonics Research 10(12), 2809-2815 (2022); Photonics Research 10(1), 21-32 (2022); Laser & Photonics Reviews 16(6), 2100638 (2022); Laser & Photonics Reviews 17(11), 2300274 (2023); and Laser & Photonics Reviews 16(6), 2100427 (2022).

Response: Thank you for your suggestion. As we argue in the manuscript this is a review of the UX factors when using immersive VR, so we do not need to specify which specific device we intend to use as this is not the scope of the review. 

Further, we consider that the suggested references are irrelevant to our manuscript and are not in line with the scope of the manuscript. 

Reviewer 2 Report

Comments and Suggestions for Authors

All the modification requested were addressed. 

Author Response

Thank you for your comments

Reviewer 3 Report

Comments and Suggestions for Authors

no more comments

Author Response

Thank you for your comments

Reviewer 4 Report

Comments and Suggestions for Authors

Dear authors,

The changes made to this manuscript have been considered significant and have contributed to its scientific contribution. 

Good luck!

Author Response

Thank you for your comment