Immersive Virtual Reality in Psychotherapeutic Interventions for Youth with Eating Disorders: A Pilot Study in a Rural Context

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The article is devoted to an experimental study on the effects of virtual reality for the psychotherapy of eating disorders. From the point of view of relevance, the topic is interesting, since virtual reality of action is used for a complex effect on the human psyche and can have a positive effect on his well-being. 
However, due to the small sample size (5 people in each group), the study can be very dependent on the individual characteristics of each participant. However, I see the following improvement trajectory, as it can still be useful in this subject area.:
- to describe in more detail the research methodology, including algorithms and methods graphically, since the main value should be an approach to organizing human impact (to justify the timing, periods of impact, technologies and tools used, metrics that are recorded from a person for subsequent analysis) 
- to describe in more detail the description of the software and the conditions of the experiment in the main article, the software development process, and the features that need to be taken into account in it for effective use in the treatment of eating disorders (i.e., it is necessary to show exactly the specifics of the software)

Other, less critical comments:
- Tables 1 and 2 lack the calculation of statistical significance between samples, for example, Mann Whitney, Kruskell, etc.
- it is not very clear from the conclusions whether a positive effect has been obtained from exposure to virtual reality? The anxiety level has increased, is it good for the participants of the experiment? It is unclear whether the attitude towards the weight problem has changed in the control group. 

Thus, the research has prospects, but in its current form it requires serious revision, since it is unclear what scientific novelty and contribution to the subject area.

Author Response

Comment 1.1. - to describe in more detail the research methodology, including algorithms and methods graphically, since the main value should be an approach to organizing human impact (to justify the timing, periods of impact, technologies and tools used, metrics that are recorded from a person for subsequent analysis) 

Authors 1.1: Thank you for your constructive comments. In response, the manuscript has been revised to improve the methodological clarity and completeness. Specifically, a table has been added for each session to illustrate the structure and content of the intervention. The duration of exposure was recorded for all sessions. Additional details have been included regarding the metrics collected, and new figures and data have been incorporated to support the description of the procedures and tools used.

Comment 1.2- to describe in more detail the description of the software and the conditions of the experiment in the main article, the software development process, and the features that need to be taken into account in it for effective use in the treatment of eating disorders (i.e., it is necessary to show exactly the specifics of the software)

Authors 1.2: We have expanded the description of the software in the Materials section, specifying that it is based on the proprietary platform and including additional images in the Appendix.

Other, less critical comments:
Comment 1.3- Tables 1 and 2 lack the calculation of statistical significance between samples, for example, Mann Whitney, Kruskell, etc.

Authors 1.3: We have included Mann-Whitney U tests to compare the control and experimental groups both at pre- and post-intervention stages, as suggested. These analyses were applied to the main outcome variables: BMI and STAI (State and Trait anxiety). We have reported U values, p-values, and effect sizes (r) for each comparison in the results section and in a new supplementary table.

Comment 1.4- it is not very clear from the conclusions whether a positive effect has been obtained from exposure to virtual reality? The anxiety level has increased, is it good for the participants of the experiment? It is unclear whether the attitude towards the weight problem has changed in the control group. 

Authors 1.4: We have clarified the conclusions in the revised manuscript to emphasize that the increase in anxiety—especially in the clinical group—can be interpreted as a therapeutic activation. This is consistent with exposure-based interventions, where a controlled and safe increase in emotional arousal (such as anxiety) is expected as part of the processing and restructuring of distorted perceptions. The exposure to the virtual body and weight-related environments likely triggered these responses, which are necessary steps toward body image recalibration.

We have updated the final paragraph of the conclusions to better reflect these points and to clearly communicate that the observed effects—though preliminary—suggest potential for using immersive virtual reality in therapeutic settings addressing body image and eating disorders.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The study is relevant. Eating disorders among youth and technological interventions in rural settings is important. The integration of IVR and remote therapy via 5G in a rural ED setting is relatively novel.

The methodology is acceptable but suffers from extremely limited sample size (n=10) and non-random assignment, which greatly limits generalizability.

The results are promising, but conclusions are overreaching in tone. The anxiety increase is interpreted constructively, but alternative explanations (distress) should be considered.

Writing is generally strong, but overuses jargon and lacks conciseness. Some redundancy exists.

Line 28-30: “increased anxiety levels after VR exposure” could be misinterpreted as a positive outcome.

Line 36: The phrase “internal body image updating” should be defined.

Line 135: Please justify nNon-randomized assignment or acknowledge it as a design limitation in Discussion.

Line 302–312: Clarify if the Brown Symptomatology Score and SSQ are separate measures of cybersickness.

Line 389: Is the recruitment of mainly female participants purposefully or randomly? It could be interesting for analyzing gender disparity.

Line 421: Figura => Figure.

Line 419–450: Trait and state anxiety increases are interpreted as expected but the reasoning could be expanded to acknowledge that high anxiety may deter continued use.

Table 1-2 : To make sure comparisons are statistically significant. please run tests to compare pre- versus post- (paired t-test or Wilcoxon) or between group (t-test of Mann-Whitney U test). With such a small sample, any statistical test has low power. It's better to present effect sizes (e.g., Cohen’s d or rank-biserial correlation) alongside p-values.

Line 457–459: Median SSQ increased yet is still interpreted as improved tolerance, this needs clarification.

Line 537–551: While VR likely contributed to changes in perceived BMI, you may over-attribute causality given the absence of statistical testing or qualitative feedback.

Line 552–567: Claim that anxiety increased due to therapeutic confrontation is speculative. Include alternative explanations, such as VR-induced distress or tech unfamiliarity.

Line 664: suggestion:  “paradigm shift” =>  “emerging approach.”.

Author Response

Comment 2.1. The results are promising, but conclusions are overreaching in tone. The anxiety increase is interpreted constructively, but alternative explanations (distress) should be considered.

Authors 2.1: Thank you for your observation. In response, we have included in the discussion that the observed increase in anxiety may not only reflect a constructive therapeutic effect, but also a possible sign of temporary distress.

Comment 2.2. Line 28-30: “increased anxiety levels after VR exposure” could be misinterpreted as a positive outcome.

Authors 2.2: In response, we have revised the final paragraph of the abstract to avoid any overly positive interpretation of the anxiety results. We now clarify that the observed increase in anxiety levels, particularly in the experimental group, should be interpreted with caution. It may reflect both a therapeutic response and temporary emotional discomfort.

Comment 2.3. Line 36: The phrase “internal body image updating” should be defined.

Authors 2.3: Thank you for your observation. We agree that the phrase “internal body image updating” could lead to ambiguity. We have replaced it with a clearer and more descriptive explanation: “helping individuals gain a more accurate perception of their own body.” This revision avoids jargon and ensures the concept is easily understood.

 

Comment 2.4. Line 135: Please justify nNon-randomized assignment or acknowledge it as a design limitation in Discussion.

Authors 2.4: Thank you for your observation. That participants were not randomly assigned. This has now been clearly stated in the Discussion section, including the justification related to the software license constraints and participant availability. We also note this as a limitation that may affect the generalizability of the findings.

Comment 2.5. Line 302–312: Clarify if the Brown Symptomatology Score and SSQ are separate measures of cybersickness.

Authors 2.5: Thank you for this observation regarding the assessment of cybersickness. We confirm that the Brown Symptomatology Score and the Simulator Sickness Questionnaire (SSQ) are separate measures. Specifically, the SSQ was used to record the frequency and intensity of cybersickness symptoms before and after each VR session. The SSQ does not have established cut-off scores to categorize the severity of symptoms. For this reason, we contacted the authors of the Spanish adaptation of the SSQ to request further guidance on interpretation. Based on their recommendations, we referred to the study by Brown et al. (2022), which proposes descriptive thresholds to help classify symptom severity in clinical and research contexts. We have clarified this distinction in the manuscript to avoid any confusion and to ensure that readers understand that the SSQ was the primary instrument to measure symptoms, while the Brown Symptomatology Score provided an additional framework to describe the clinical relevance of the reported scores.

Comment 2.6. Line 389: Is the recruitment of mainly female participants purposefully or randomly? It could be interesting for analyzing gender disparity.

Authors 2.6: We appreciate your follow-up regarding the gender distribution of the sample. The predominance of female participants was not the result of any purposeful selection. Recruitment was carried out consecutively, including all patients who met the inclusion criteria as they presented to the mental health center during the study period. This gender distribution reflects the higher prevalence of eating disorders among adolescent females, which is well-documented in the literature.

While this proportion aligns with the epidemiology of eating disorders, we agree that it may limit the possibility of exploring gender differences within this pilot study. We have now included this clarification and acknowledged this limitation in the manuscript.

Comment 2.7. Line 421: Figura => Figure.

Authors 2.7: We thank the reviewer for pointing this out. The term "Figura" has now been corrected to "Figure" in line 421.

Comment 2.8. Line 419–450: Trait and state anxiety increases are interpreted as expected but the reasoning could be expanded to acknowledge that high anxiety may deter continued use.

Authors 2.8: Thank you for this valuable observation. We agree that although increases in state and trait anxiety were anticipated as part of the therapeutic exposure process, high anxiety levels may also represent a barrier to continued engagement with the intervention. We have now expanded the Discussion section to address this point, highlighting that elevated distress could discourage sustained use and that monitoring and supportive strategies may be necessary to ensure adherence. This consideration has also been briefly reflected in the Conclusions section.

Comment 2.9. Table 1-2 : To make sure comparisons are statistically significant. please run tests to compare pre- versus post- (paired t-test or Wilcoxon) or between group (t-test of Mann-Whitney U test). With such a small sample, any statistical test has low power. It's better to present effect sizes (e.g., Cohen’s d or rank-biserial correlation) alongside p-values.

Authors 2.9: We have addressed this comment by conducting both within-group (pre vs. post) and between-group comparisons using non-parametric tests appropriate for small sample sizes. Specifically, we used the Wilcoxon signed-rank test for within-group comparisons and the Mann-Whitney U test for between-group analyses. For each test, we have reported p-values and effect sizes (rank-biserial correlation). The results are summarized in the table below, which has been included in the revised manuscript.

Comment 2.10. Line 457–459: Median SSQ increased yet is still interpreted as improved tolerance, this needs clarification.

Authors 2.10: We have modified the text in the results

Regarding symptoms of cyber-sickness (SSQ) in the four sessions of the case group, the mean scores indicate a general trend of decreasing discomfort across sessions: Session 1 (3 ± 3.51), Session 2 (1 ± 1.92), Session 3 (1 ± 1.09), and Session 4 (1 ± 0.50). Despite this downward trend in mean values, the median SSQ score slightly increased from 1.95 in the first phase to 2.47 in the last phase. This apparent contradiction is due to a single participant reporting a localized increase in symptoms during the final session, which influenced the central tendency despite overall low symptom levels. Importantly, all SSQ scores remained within the range considered as minimal or clinically insignificant, suggesting that the intervention was generally well tolerated.

Comment 2.11. Line 537–551: While VR likely contributed to changes in perceived BMI, you may over-attribute causality given the absence of statistical testing or qualitative feedback.

Authors 2.11: We have modified the text in the discussion:

In the global analysis of BMI-related variables, a general trend was observed: actual and perceived BMI slightly increased, while desired BMI decreased. These changes may indicate a gradual shift in body perception among participants. In the case group, perceived BMI moved closer to the range considered healthy, and reported healthy BMI also increased, while desired BMI remained stable. This pattern could suggest a better alignment between body self-perception and health norms. However, as no statistical tests or qualitative feedback were used to assess causality, these interpretations should be approached with caution. In the control group, BMI variables remained relatively stable, suggesting limited impact from standard treatment alone. Taken together, these observations may support the potential of immersive VR to influence body-related attitudes, although further research with larger samples and qualitative insights is needed to confirm these preliminary results.

Comment 2.12. Line 552–567: Claim that anxiety increased due to therapeutic confrontation is speculative. Include alternative explanations, such as VR-induced distress or tech unfamiliarity.

Authors 2.12: We have modified the text in the discussion:

A general increase in both state and trait anxiety was observed, particularly in the case group. Although this may seem unexpected, similar increases have been reported in early stages of exposure-based interventions. Being exposed to one's own body image—especially when there is dissatisfaction or distortion—can generate strong emotional responses, including fear of weight gain and discomfort with physical appearance. These reactions may indicate the start of a deeper emotional and cognitive engagement with body-related concerns. Previous studies suggest that such emotional activation can contribute to long-term improvement by initiating processes like habituation and adjustment of body perception

 Nevertheless, other explanations must be considered. The increase in anxiety might also be related to general emotional distress caused by the intensity of the experience, unfamiliarity with the technology, or discomfort using virtual reality equipment. Given the small sample and short follow-up, it is not possible to determine whether the anxiety increase reflects therapeutic progress or a temporary stress response. Further research is needed to explore this question.

Comment 2.13. Line 664: suggestion:  “paradigm shift” =>  “emerging approach.”.

Authors 2.13: We have incorporated the modification into the text.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

1. The procedure of measures should be described in more detail. 

2. Fig. 2 could be better presented. 

3. Fig. 3 needs clarification and more analysis. 

4. The authors should focus on the objectives of this research work. What is the superiority of such research compared to other related works?

5. Some future directions can be proposed in the end of the manuscript. 

 

 

Comments on the Quality of English Language

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Author Response

Comment 3.1. The procedure of measures should be described in more detail. 

Authors 3.1: We appreciate your comments. In response, we have expanded the description of the measurement procedure in the Methods section to provide greater detail on how the assessments were conducted during the intervention. Additionally, we have included illustrative figures to visually represent the process and enhance understanding of the remote IVR setup, and the tools used for data collection.

Comment 3.2. Fig. 2 could be better presented. 

Authors 3.2: We have revised Figure 2 to improve clarity and visual consistency. The new version separates the State and Trait Anxiety results into distinct visual elements using a unified bar chart format, making comparisons between pre- and post-intervention, and across groups, more accessible and easier to interpret.

Comment 3.3. Fig. 3 needs clarification and more analysis. 

Authors 3.3: Thank you for your observation. We have updated Figure 3 to improve clarity by adopting a unified bar chart format that distinguishes discomfort levels by session and VR scenario. The revised figure facilitates a clearer comparison of emotional responses across participants. Additionally, we expanded the accompanying text to highlight individual variability and the relevance of scenario-specific emotional activation, reinforcing the need for personalized therapeutic pacing.

Comment 4.4. The authors should focus on the objectives of this research work. What is the superiority of such research compared to other related works?

Authors 4.4: Thank you for your observation. We have revised the introduction to better clarify the objectives of the study and to explain how this work differs from previous research. Specifically, we now highlight that this pilot study combines immersive virtual reality with remote delivery in a rural adolescent population with eating disorders—an approach that has not been addressed in earlier studies. This combination allows us to explore both the emotional impact and the technical feasibility of remote VR therapy in underserved settings.

Comment 5.5. Some future directions can be proposed in the end of the manuscript. 

Authors 5.5: Thank you for your suggestion. We have added a new section at the end of the manuscript titled “Future Directions”, where we outline possible next steps for research based on the findings of this pilot study.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The authors have made significant improvements to the text, and the work has been significantly improved in terms of methodological transparency, the detail of the software used, and statistical analysis. However, some of the comments have been partially eliminated, and some of the issues related to scientific novelty and interpretation of anxiety still need to be clarified. A minor revision of the current version is required in the following areas:
- It seems to me that the A4 fugure deserves more attention and transfer to the main part of the work, since it also concentrates the author's approach (algorithm). However, I did not understand why it is duplicated in the application. 
- It is a bit strange to use the notation c/d instead of a/b in Figure 3.
- Some sources have a very strange appearance, for example 28.
- There are some typos in the text, for example, “scenari” in table 1.

 

Author Response

We would like to sincerely thank Reviewer for the careful reading of our manuscript and the constructive feedback provided. We are grateful for the recognition of the improvements made in terms of methodological transparency, detail of the software used, and statistical analysis. We have carefully considered all remaining suggestions and concerns and have revised the manuscript accordingly.

Below, we provide a point-by-point response to each comment. All changes made in response to the reviewer’s observations are marked in the revised manuscript. Line numbers cited below refer to the revised version.

Comment 1:
The authors have made significant improvements to the text, and the work has been significantly improved in terms of methodological transparency, the detail of the software used, and statistical analysis. However, some of the comments have been partially eliminated, and some of the issues related to scientific novelty and interpretation of anxiety still need to be clarified.

Authors’ response 1:
Thank you for your comment and for acknowledging the improvements made. The authors have carefully reviewed the text and improved it according to your recommendations.

 

Comment 2:
It seems to me that the A4 figure deserves more attention and transfer to the main part of the work, since it also concentrates the author's approach (algorithm). However, I did not understand why it is duplicated in the application.

Authors’ response 2:
Thank you for this observation. Following the reviewer’s suggestion, we have now moved this figure into the main text, and removed its duplicate appearance in the appendix to avoid redundancy.

 

Comment 3:
It is a bit strange to use the notation c/d instead of a/b in Figure 3.

Authors’ response 3:
We appreciate the reviewer’s attention to detail. The notation c/d in Figure 3 was used unintentionally and has now been corrected to the conventional a/b format for consistency and clarity across the manuscript (see revised Figure 3).

 

Comment 4:
Some sources have a very strange appearance, for example 28.

Authors’ response 4:
Thank you for pointing this out. We have carefully reviewed all references and corrected the formatting issues, including the one noted in reference [28]. The updated reference list now follows the required style guide and has been double-checked for consistency and accuracy.

 

Comment 5:
There are some typos in the text, for example, “scenari” in table 1.

Authors’ response 5:
We appreciate the reviewer’s careful reading. We have corrected the typo “scenari” to “scenario” in Table 1, and have conducted a thorough proofreading of the manuscript to eliminate any additional typographical errors.

Reviewer 2 Report

Comments and Suggestions for Authors

The authors responded adequately to my comments. I have no further comments. 

Author Response

We appreciate the review and the comments provided, which have contributed to the improvement of the manuscript.