VISCERAL SENSITIVITY INDEX (VSI-IT): Italian Adaptation and Validation

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The current study aimed to test the psychometric properties of the Italian version of the Visceral Sensitivity Index (VSI). Results suggested that the VSI is a valid and realiable instrument which might be employed in assessing gastrointestinal-specific anxiety among Italian patients with Chronic Inflammatory Bowel Diseases. It is noteworthy that the study involved both patients with Chronic Inflammatory Bowel Diseases and individuals from the community, and that Authors performed adequate statistical analyses to test the psychometric properties of the Italian version of the VSI. However, there are some limitations that should be addressed to evaluate the suitability of the current manuscript for publication.

Abstract

1. Authors wrote: “The scale proved sensitive in detecting significant differences in visceral sensitivity among groups, highlighting its utility as a clinical and research assessment tool. Specifically, the Italian VSI exhibited a unidimensional factorial structure and maintained a strong correlation with other measures of anxiety and the severity of gastrointestinal symptoms, confirming its role in enhancing the understanding and management of IBS and IBD in Italy.” It is advisable for Authors to report additional information on recruited groups. Also, they did not investigate correlations between scores on VSI and scores on other measures of anxiety and the severity of gastrointestinal symptoms. Accordingly, it is advisable for Authors to revise the abstract by accurately reporting their results.

Introduction

2. It is reccomended that Authors report the full name of the "Visceral Sensitivity Index" when they mention it for the first time.

3. Authors wrote: “The VSI specifically focuses on symptom-related anxiety known as Gastrointestinal-Specific Anxiety (GSA). This type of anxiety is characterized by fear and apprehension regarding visceral sensations and symptoms, which can significantly impact the patients’ quality of life.” It is advisable for Authors to support their statements by citing adequate references.

4. Authors should report the rationale to investigate the correlations between scores on VSI scale and scores on Multidimensional Assessment of Interoceptive Awareness (MAIA) subscales.

Materials and Methods

5. In Participants section, Authors wrote: “The study involved 500 Italian-speaking participants, including 108 males, 391 female, and 1 non-binary individual, with an age range from 18 to 85 years (M = 35.04; SD = 164 13.29). Two groups were formed, including a control group with healthy subjects (164 participants) and an experimental group consisting of patients with Chronic Inflammatory Bowel Diseases (180 UC; 111 CD; 34 IBS; 11 awaiting diagnosis) in either an active 167 state of the disease or remission. The first criterion for questionnaire participation was reporting an age of at least 18 years.” It is advisable for Authors to report sociodemographic information for individuals from the community and patients with Chronic Inflammatory Bowel Diseases, including patients with Crohn’s Disease, patients with Ulcerative Rectocolitis, patients with Irritable Bowel Syndrome and other patients, respectively. This may ensure the replicability of the study.

6. Moreover, it is reccomended that Authors do not use the term “experimental group” to refer to group comprising patients with Chronic Inflammatory Bowel Diseases. In fact, the current study did not involve an experimental design.

7. In the Instruments section, Authors wrote: “Given the total score, a value greater than 37.5 has been chosen to indicate an increased VSI in individuals [10].” It is advisable for Authors to revise the mentioned reference.

8. In the Instruments section, it is advisable for Authors to report additional information on the MAIA, such as an example of an item, the Likert scale on which each item is rated, its psychometric properties, and references to its Italian adaptation.

9. In the Statistical Analysis section, it is advisable for Authors to provide additional information in order to improve the readability of the manuscript. Accordingly, Authors should illustrate which psychometric properties were investigated through each statistical analysis. Also, they should report which groups were considered to perform each statistical analysis.

Results

10. In the Validity and reliability of VSI-IT section, Authors wrote: “items with higher factor loadings (exceeding 0.8), such as Item __"I often worry about belly problems" and Item __"I have difficulty 243 enjoying myself because I can't take my mind off belly discomfort." reflect deep and persistent concerns regarding abdominal discomfort and its impact on daily life. At the same time, even items with slightly lower factor loadings, like Item __"I am constantly aware of 246 the sensations I have in my belly." represent relevant aspects of specific anxiety for gastrointestinal symptoms, indicating high awareness and concern for bodily sensations.” It is advisable for Authors to indicate the numbers of mentioned items to improve the readability of the manuscript.

Discussion

11. In the Limitations section, Authors wrote: “Furthermore, comparisons with other studies are only partially possible, as in this study, the assessment of interoceptive awareness was preferred over clinical scales assessing anxiety and depression.” It is advisable for Authors to revise this statement in order to clarify why the comparison of the current study with other studies is only partially possible.

Other remarks

12. It is recommended that a native English speaker revises the manuscript.

Author Response

Dear reviewer, thank you for sharing the feedback and recommendations regarding your manuscript. We really appreciate the time you spent and the constructive tone you used.

 

Here's how we've addressed each of the points mentioned:

1. Abstract: We've updated the abstract to include detailed information about the groups recruited for the study (IBD > Crohn and UC ; IBS). We also specified the correlations between scores on the VSI and other measures of interoceptive awareness and not anxiety, along with the severity of gastrointestinal symptoms to accurately reflect our findings.
2. Introduction: We've included the full name "Visceral Sensitivity Index" at its first mention in the introduction, ensuring clarity for readers unfamiliar with the abbreviation.
3. We've supported our statements about GSA by citing properly relevant studies that discuss its impact on quality of life, providing a robust theoretical foundation for our research.
4. We've clearly outlined the rationale behind investigating the correlations between VSI scores and the Multidimensional Assessment of Interoceptive Awareness (MAIA) subscales, explaining the expected insights from this analysis before presenting instruments.
5. Results: The manuscript now includes comprehensive sociodemographic details for both community individuals and various patient groups, enhancing the replicability of our study, a new table was entered (Table 1).
6. We've replaced the term "experimental group" with "patient group" to more accurately reflect the design of our study, which does not involve experimental manipulations. Thank you for noticing.
7. We've revised the reference associated with the VSI scoring threshold to ensure accuracy and reliability of the information provided.
8. Additional details about the MAIA, including sample items, the Likert scale used, its psychometric properties, and references to its Italian version, as part of a worldwide project of University of San Francisco, have been thoroughly included.
9. We've enhanced the section on statistical analysis by specifying which psychometric properties were assessed through each analysis and detailing the groups considered in each analysis. We replaced and improved tables and figures to enhance clarity and coherence.
10. We've added the specific item numbers in the VSI to improve readability and allow readers to easily understand which items correspond to higher or lower factor loadings.
11. Discussion: We've revised the statement regarding the limitations of comparing our study with others to better explain the preference for interoceptive awareness measures over clinical scales and difficulty in comparisons.
12. We've had the manuscript reviewed by a native English speaker to ensure the language is clear, precise, and professional.

We hope these modifications address the concerns raised and enhance the quality and clarity of the manuscript. Thank you for your constructive feedback.

Reviewer 2 Report

Comments and Suggestions for Authors

Thr paper is very well written and a nicely performed validation study.  Furthermore I have a few suggestions that the authors may consider. In the abstract 'other chronic inflammatory bowel diseases' has been given the abbreviation IBD. IBD is in general only used for Crohn's disease (CD) and ulcerative colitis (UC) and not other inflammatory bowel diseases as such. In the methods section a comment on why a mixed population was included should be described. Also I miss a reference to the prevalence of IBS symptoms in patients with IBD (i.e a review by Fairbrass KM, et al 2020). This should be revisited in the discussion concerning potential overlap of symptoms between the groups. Figures and tables are excellent. 

Comments on the Quality of English Language

I have detected only one minor spelling mistake (English, line 64, page 2).

Author Response

Thank you very much for your kind words about our paper and for the insightful suggestions you've provided. We have taken your feedback into consideration and have made the following changes:

1. Abstract: We've revised the use of the abbreviation "IBD" in the abstract to specifically refer to Crohn's Disease (CD) and Ulcerative Colitis (UC), as suggested, to ensure accuracy and clarity.
2. In the methods section, we've added a detailed explanation of why a mixed population was included, highlighting the benefits of this approach in understanding the broader application and impact of the VSI in diverse clinical settings.
3. Reference: We've incorporated the suggested reference by Fairbrass KM, et al. 2020, to discuss the prevalence of IBS symptoms in patients with IBD. This addition strengthens the discussion on the potential symptom overlap, providing a more comprehensive analysis of the issues at hand.

Your feedback has been invaluable in enhancing the quality and completeness of our manuscript. Thank you again for your constructive and detailed comments.

 

Reviewer 3 Report

Comments and Suggestions for Authors

Abstract: Overall, the abstract was well written and concise. However, the objective/ goal of the study was briefly discussed, but it needs to be explicitly stated somewhere in the abstract. Additionally, it is discussed the VSI is used in IBS and IBD in the first sentence. Then, the study methodology is explained and uses patients with Ulcerative Colitis and Crohn’s disease. It should be briefly mentioned that Ulcerative Colitis and Crohn’s Disease are types of IBD to support why the VSI is the correct tool to use. Additionally, please see minor edits below.

Line 35: “Reference population” Is this referring to Italian patients? It is unclear from the wording.

Line 36: “Healthy controls” Is this patients without Ulcerative Colitis and Crohn’s Disease?

 

Introduction: The introduction was well written and summarized other literature regarding implementing the VSI in other languages and the success. The first sentence of the introduction should orient readers to the disease state and plainly introduce the topic. To strengthen the introduction, there should be more information about the disease state. For instance, the manuscript does not state the prevalence of Ulcerative Colitis in Italy. Lines 75-79 present the validation of the tool and belong to the results section. However, the authors do not clarify whether these results belong to their study or another study. Furthermore, the lack of references makes the paragraph weaker.

There are many paragraphs that must be referenced to avoid plagiarism. For example, Line 80-96, Should the reader understand that the data presented belonged to reference 4? If so, the authors must cite it appropriately. Furthermore, the following paragraphs do not have any citations. Please use references appropriately.  Lines 49-56 and Lines 98-132 have lack of references.

Additionally, the objectives were clearly defined at the end of the introduction, along with the gap in literature and what this study would contribute. Please see minor edits below.

Line 64: “Englis” Should be English

Methods: The methods section has significant flaws. For example, the study received the approval of the Polish Ethics Committee. However, the manuscript's introduction focused on Italy. If there was a collaboration between these countries, it must be specified in the introduction and the methodology.

Additionally, the study did not clearly define the MAIA and its usage. Expanding on which questionaries were used, how often, and more information about the study protocol would strengthen the methods section.

Another weakness is the lack of Factor Analysis for validation of the instrument.

 

Please address the following major concerns:

Recruitment: How were the participants recruited? Was bias avoided? What was the power of the study (for instance, why was 500 used)?

Line 165: “Healthy individuals”  It is recommended to expand on this. For instance, are these patients considered healthy due to not having Ulcerative Colitis or Crohn’s disease?

Additionally, please see minor grammar edits below:

Line 147: “February 13 to March 23.2023” There should be a comma after 23 instead of a period. Additionally, to avoid confusion, it is recommended to put the year after February 13.

Line 150: “followed by a review by a professional in the field” It is recommended that instead of the second by, using the word “from.”

Line 163: “391 female” should be females

Line 167: “180 UC; 111 CD”  Abbreviations must be defined previously in the text before you can use them.

Line 168: “Criterion” Is this supposed to be criteria?

Line 170-183: The paragraph before this one was written in the past tense, then this paragraph starts with present tense. At the end of the paragraph, it shifts back to past tense. It is recommended to stay in the same tense throughout the paragraph.

 

Results

The authors explain some measurements; however, the lack of Factor Analysis weakens this section.

Although the authors include tables and figures, there are major concerns regarding interpretation of them. For example, Table 1 presents “item numbers” without an explanation of what the items are measuring.

Another failure of this study is the discrepancies between methods and results sections. Since the authors do not present any information in results section about what they are measuring and what statistical analysis was performed, the reader is unable to interpret the statistical figures 1 and 2.

Furthermore, the tables and figures require major edits to increase consistency in labeling, for example “Table 2.” Is labeled with a period, while “Table 3 –“  is labeled with a hyphen, and then “Table 4.” returns to the period-style labeling. Overall, the results section lacks other results to validate the scale.

Another major concern is in Line 302: There is no Table 5 labeled in this article, readers do not know where they can find the correlation table.

Additionally, please see minor grammar edits below:

Line 224: of the scale,

Line 243: Should the Item numbers of these items be included? Or is the __ intentional? The item explanation is very effectively explained but the __s take away from the quality explanation

Line 246: Same as above regarding the __ after Item

Line 262: The paragraph could potentially benefit from a sentence further explaining the Bonferroni correction, like how Cronbach’s Alpha value was explained in 3.1

Line 269: significant,

Line 277: The labeling for the other tables in the article are above the associated tables. Is this Table 2 referencing the boxplots above or the VSI-IT SD and Ms underneath? If it is representing the VSI-IT SD and M table it should be centered and would potentially benefit from another space separating it from the above figures

Line 278: The labeling is not consistent with the other tables, all other tables “Table 1.”, “Table 2.” utilize a period and this utilizes a hyphen. Consider revising for consistency.

Lines 291-294: This sentence about future research may be more useful in the discussion section

Line 318: The table under this sentence is not labeled at all, this must be labeled

 

Discussion

The discussion section has many flaws. For example, the section starts with, "This study aimed to examine the psychometric characteristics of the VSI-IT in patients with IBS and IBD (Inflammatory Bowel Disease."  This sentence misinformed the reader since the authors did not survey the Italian population diagnosed with IBD. The authors must rephrase to represent their sample accurately.

Another primary concern is the lack of statistical analysis. Although the authors claim "positive statistical outcomes," they only present the Cronbach alfa.  With respect to the author's work, no other statistical outcomes are presented in this study. The manuscript presented descriptive statistics that cannot be misinterpreted as Factor Analysis.

Furthermore, this section lacks a discussion of future research, including recommendations for future studies or analyses. The only mention of another potential study was in Line 368, which requires additional information as to why the exploration of diagnostic capabilities of the VSI in patients awaiting diagnosis is interesting. Additionally, further elaboration on the implications of the results and why the findings about the VSI tool matter would benefit this section. 

Another weakness of this study is the lack of comparison to other validated studies and their statistical analysis. Readers are looking for new insights or more explicit understandings of previous data that is not mentioned in the discussion. 

Line 322: IBD has already been defined in the abstract, the (Inflammatory Bowel Disease) can be removed

Line 350: VSI has already been defined, (Visceral Sensitivity Index) can be removed

Conclusions Although the first sentence of the conclusion is very strong and succinctly summarizes the utility of their VSI tool, it is unsubstantiated by the lack of statistical analysis performed. Additionally, the authors highlight how utilizing and understanding the results of their tool can positively influence quality of life.

Line 378: VSI has already been defined, (Visceral Sensitivity Index) can be removed

Line 378-379: “The VSI (Visceral Sensitivity Index) represents a fundamental tool for patients as it provides a specific and personalized assessment of their gastrointestinal sensitivity.” This seems to be somewhat of a new idea since it was not mentioned in the discussion. It was discussed once in the introduction, but this seems to be a major result that is understated. This idea could be incorporated into the results section and then elaborated on in the discussion so that it is clear that this is what the authors concluded.

Comments on the Quality of English Language

Line 147: “February 13 to March 23.2023” There should be a comma after 23 instead of a period. Additionally, to avoid confusion, it is recommended to put the year after February 13.

Line 150: “followed by a review by a professional in the field” It is recommended that instead of the second by, using the word “from.”

Line 163: “391 female” should be females

Line 167: “180 UC; 111 CD”  Abbreviations must be defined previously in the text before you can use them.

Line 168: “Criterion” Is this supposed to be criteria?

Author Response

Dear reviewer, thank you for your thorough and constructive feedback.

We have addressed each of your points to improve the clarity and rigor of our manuscript:

Abstract:

• We explicitly stated the objective of the study in the abstract to clarify the aim clearly and concisely.
• We added a brief explanation that Ulcerative Colitis and Crohn's Disease are types of IBD, supporting the use of the VSI for these conditions.

Minor Edits in Abstract:

• Line 35: Clarified that "reference population" refers to Italian-speaking individuals.
• Line 36: Specified that "healthy controls" are individuals without any diagnoses.

Introduction:

• Enhanced the first sentence to better introduce the disease state and set the stage for the discussion on VSI.
• Included prevalence data for Ulcerative Colitis in Italy to provide context.
• Moved instruments details from lines 75-79 to the results section and clearly indicated whether the results pertain to our study or referenced literature.
• Strengthened citations across the introduction to ensure all data is properly attributed and to avoid plagiarism.

Methods:

• [We have clarified the involvement of the Polish Ethics Committee with the Editorial office, as a results of a blind procedure to ensure ethics standards, because of conflict of interest with the Local Ethic Committee].
• Expanded on the use of the MAIA, including specifics and information about the questionnaire and study protocol.
• Addressed the lack of informations about Factor Analysis by including new details for validating the instrument.

Recruitment and Study Power:

• Detailed the recruitment process, addressed potential biases, and explained the rationale behind the sample size of 500 participants (by adding calculation of the statistical power of the sample).

Minor Grammar Edits in Methods:

• Corrected grammatical errors and inconsistencies in dates, phrases, and tense usage.

Results:

• Included Factor Analysis to strengthen this section.
• Improved the clarity of tables and figures by standardizing labeling and providing detailed item descriptions where needed.

Discussion:

• Corrected the statement about the population surveyed to accurately reflect those diagnosed with IBD.
• Detailed the statistical analyses performed beyond Cronbach's alpha, ensuring a robust presentation of results.
• Expanded the discussion of future research and its implications, adding depth to the potential applications of the VSI in the diagnostic phase.

Conclusions:

• Strengthened the conclusion by substantiating the utility of the VSI with detailed statistical analysis.
• Ensured consistency in the use of abbreviations and integrated key findings from the discussion into the conclusion for a coherent summary.

These modifications enhance the manuscript significantly, addressing each of your concerns while maintaining the integrity and scientific rigor of our work.

Thank you again for your invaluable feedback. We hope you could be satisfied with this carefully revised version.

 

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

I think that Authors properly revised the manuscript in accordance with the Reviewer’s comments and suggestions, providing an improved version of it. However, there are still minor points that needs to be addressed:

1. In the Introduction section, Authors wrote: “In clinical settings, a pronounced focus on physical sensations is commonly associated with disorders such as anxiety, hypervigilance, somatization, and hypochondriasis [4]. This type of heightened interoceptive awareness is generally viewed as maladaptive and potentially harmful. Interoception, which involves the nervous system's capacity to sense, decode, and integrate signals from within the body, has gained prominence as a crucial area of study in the context of mind-body interactions and psychosomatics. Being a key construct in this field, interoceptive accuracy—recently also termed interoceptive sensitivity—plays a vital role in research into how individuals perceive internal bodily states [7]”. It is advisable for Authors to report more references supporting their statements to provide a more comprehensive review of previous literature.

2. In the Instruments section, Authors should provide Cronbach’s alpha coefficients of the MAIA subscales to provide information on their internal consistency in the sample of the current study.

3. In the Results section, Authors wrote: “The Comparative Fit Index (CFI), Tucker-Lewis Index (TLI) and Standardized Root Mean Square Residual (SRMR) scores of the EFA solution were 0.909, 0.894 and 0.046, respectively. These scores are close or above the generally acceptable level of 0.90 for CFI and TLI, while below the upper-threshold of 0.08 for SRMR, indicating that the computed model was reasonably able to capture the underlying factor structure of the variables, while also indicating that the variance explained by the model was significantly higher than random”. It is advisable for Authors support their statements mentioning adequate references.

4. In the Discussion section, Authors wrote: “Factor Analysis revealed a strong unidimensionality in the construct measured by the VSI, with all 15 items showing high factor loadings”. It is advisable for Authors to do not overestimate their results. In fact, the indices of fit of the model did not support a “strong” unidimensionality of the instrument, as they were close to cutoffs for an acceptable factor solution.

5. In the Discussion section, it is advisable for Authors to discuss both the negative and positive associations between VIS scores and MAIA subscales scores. This could strengthen the manuscript, clarifying the role of interoceptive awareness domains in visceral sensitivity.

6. In the Discussion section, it is recommended that Authors provide references to support the following statements: “Furthermore, comparisons with other studies are only partially possible, as in this study, the assessment of interoceptive awareness was preferred over clinical scales assessing anxiety and depression. Conversely, studies addressing interoceptive awareness using MAIA did not use the VSI”.

Author Response

Dear Reviewer,

 

Thank you for your meticulous review and constructive feedback on our manuscript. We have carefully considered each of your points and have made corresponding amendments to enhance the clarity and rigor of our work. Here are the changes and additions we have implemented in response to your suggestions:

 

1. We have expanded our review of the literature and included additional references that support our statements on the role of interoceptive awareness in clinical settings. References have been added to provide a broader context and evidence base about interoceptive awareness :

 

Davey, S., Bell, E., & Halberstadt, J. (2023). Using targeted visceroception to improve interoceptive sensibility and emotion regulation. New Ideas in Psychology, 68, 100989.

 

Calì, G., Ambrosini, E., Picconi, L., Mehling, W. E., & Committeri, G. (2015). Investigating the relationship between interoceptive accuracy, interoceptive awareness, and emotional susceptibility. Frontiers in psychology, 6, 1202.

 

 

 

2. As suggested, we have now included Cronbach’s alpha coefficients for the MAIA subscales within our sample (.86). This addition provides clarity on the internal consistency of the instruments used in our study, enhancing the reliability of our results.

 

3. We have supported our statistical findings with additional references that discuss the thresholds and implications of the Comparative Fit Index (CFI), Tucker-Lewis Index (TLI), and Standardized Root Mean Square Residual (SRMR). This ensures our discussion of the model's fit and its ability to capture the underlying factor structure is well-founded and grounded in established statistical literature:

 

Perry, J. L., Nicholls, A. R., Clough, P. J., & Crust, L. (2015). Assessing model fit: Caveats and recommendations for confirmatory factor analysis and exploratory structural equation modeling. Measurement in physical education and exercise science, 19(1), 12-21.

Montoya, A. K., & Edwards, M. C. (2021). The poor fit of model fit for selecting number of factors in exploratory factor analysis for scale evaluation. Educational and psychological measurement, 81(3), 413-440.

 

 

4. In response to your advice, we have tempered our language concerning the unidimensionality of the VSI construct measured. We now describe the factor loadings as "potential" rather than "strong" to more accurately reflect the closeness of the fit indices to their acceptable thresholds. This change avoids overestimation and aligns our discussion with the empirical data.

 

5. We have expanded our discussion to address both the negative and positive associations observed between VIS scores and MAIA subscales. This balanced discussion helps clarify the complex interplay of interoceptive awareness domains in relation to visceral sensitivity, thereby strengthening the manuscript by adding the following paragraph:

 

“The correlations between Multidimensional Assessment of Interoceptive Awareness (MAIA) subscales and the Visceral Sensitivity Index reveal insightful relationships concerning how individuals with IBD and IBS perceive and react to internal bodily signals. For instance, the positive correlation with the 'Noticing' dimension indicates that individuals more attuned to bodily sensations also report greater visceral sensitivity, highlighting a heightened worry about internal bodily states. Conversely, the negative correlation with 'Not-worrying' suggests that patients who exhibit less emotional distress or worry in response to pain or discomfort tend to perceive lower visceral sensitivity, and viceversa, possibly reflecting a coping mechanism that dampens the perception of internal discomfort. Similarly, 'Trusting' one's body, associated with a moderate negative correlation, implies that viewing the body as safe and reliable can reduce sensitivity to visceral signals, potentially offering psychological buffer against distress. On the contrary, not trusting one's body could have the opposite effect. If a person perceives their body as unsafe or unreliable, they might experience increased sensitivity to visceral signals. This hypersensitivity can amplify the perception of discomfort or pain, making the person more vulnerable to psychological stress related to unpleasant bodily sensations. In such cases, the body is not perceived as an ally but rather as a source of worry and anxiety, increasing the emotional burden and complicating the management of symptoms related to conditions like IBD and IBS. These findings underscore the interplay between cognitive, emotional, and sensory aspects of interoceptive awareness, influencing how people affected by IBD and IBS experience their internal bodily experiences.”

 

6. We have specified that we refer particularly to “validation” studies which assessed visceral sensitivity over clinical scales for anxiety and depression [1-6], or interoceptive awareness but not VSI [7-9].

 

We believe these revisions address your concerns comprehensively and enhance the manuscript significantly. We appreciate your guidance in refining our work and look forward to know if you’re satisfied with these changes.

 

Best regards,

Dr. Amelia Rizzo, PhD

Dr. Aldo Sitibondo, MD

Reviewer 3 Report

Comments and Suggestions for Authors

Although the manuscript addressed most of my concerns, the major flaws are in the graphs. For example, the titles are misleading and the axes are not labeled. 

Furthermore, the manuscript attempted to interpret the results which created more ambiguity and confusion. For example, the over usage of acronyms makes the text unreadable:" The Comparative Fit Index (CFI), Tucker-Lewis Index (TLI) and Standardized Root Mean Square Residual (SRMR) scores of the EFA solution were 0.909, 0.894 and 0.046, 302 respectively. " What do these scores mean? Is it statistically significant?

Comments on the Quality of English Language

The sentence is unfinished. "The Bartlett's test of sphericity, with an approximate chi-square value 291 of 5339.394 and p < .001,"

 Another example of unfinished sentence: The Kaiser-Meyer-Olkin Measure of Sampling Adequacy (KMO) provides another indicator of adequacy. With a value of for collected data (15 items of VSI-IT) was 0.961, it far exceeds above the acceptable minimum of 0.5, indicating that the data sampling for factor analysis is was more than adequate"

Author Response

Dear Reviewer 3,

Thank you for your continued feedback and attention to detail in reviewing our manuscript. We acknowledge the issues you've raised regarding the clarity and presentation of the graphs, as well as the interpretability of the results. We have carefully addressed these points as follows:

1. We have revised all the graphs in the manuscript. Each graph now has a clear, descriptive title and the axes are properly labeled, ensuring that they accurately represent the data discussed. With respect to version 1 please note that new graphs have also been added to enhance clarity and provide visual support for the interpretations provided in the text.
2. We have clarified the interpretation of our statistical results to reduce ambiguity. Specifically, we have revised the discussion on the meaning of the Comparative Fit Index (CFI), Tucker-Lewis Index (TLI), and Standardized Root Mean Square Residual (SRMR) scores, explaining their significance in the context of our analysis. We now provide a clearer explanation of what these indices represent, their thresholds for acceptability, and why they are relevant for evaluating the fit of our model.

We added a section that explicitly discusses the statistical significance of our findings, helping readers understand the impact and reliability of the results:

“These scores are close or above the generally acceptable level […] indicating that the computed model was reasonably able to capture the underlying factor structure of the variables, while also indicating that the variance explained by the model was significantly higher than random [13,14].”

3. We have thoroughly reviewed the manuscript for any unfinished sentences and have corrected these errors:

• The sentence discussing Bartlett's test of sphericity has been completed with appropriate statistical context to ensure it communicates the results effectively: “The Bartlett's test of sphericity, with an approximate chi-square value of 5339.394 and p < .001, confirmed that a factorial solution for these 15 items was supported.“

 

• The explanation of the Kaiser-Meyer-Olkin Measure of Sampling Adequacy (KMO) has been revised for clarity and completeness: “The Kaiser-Meyer-Olkin Measure of Sampling Adequacy (KMO) for collected data (15 items of VSI-IT) was 0.961, far above the acceptable minimum of 0.5, indicating that the data sampling for factor analysis was more than adequate.”

We believe these revisions comprehensively address the concerns you've raised in your review. We hope that these changes enhance the clarity, accuracy, and readability of our manuscript. We appreciate your guidance in improving our work and look forward to your feedback on these adjustments.

Thank you once again for your critical insights and support in refining our study. We hope you could be happy with this revised new version.

 

Best regards,

Dr. Amelia Rizzo, PhD

Dr. Aldo Sitibondo, MD

Round 3

Reviewer 3 Report

Comments and Suggestions for Authors

One crucial aspect that needs further clarification is the participant assignment process. The authors have provided a detailed power calculation for the study (n=500), which is commendable. However, it remains unclear how the participants were assigned to the control group versus the treatment group, and what led to the discrepancies in the number of participants in each group. The authors mention that “164 were in the control group” and the rest were in the treatment group. Understanding this process is vital as it directly impacts the validity of the study's results.

Another area that requires attention is the presentation of figures and tables. Currently, the figures lack an explanation of the axis, rendering them meaningless. Similarly, Table 3 does not convey any clear message, making it difficult to interpret. Recommend removing it.  Providing clear titles and explanations will make the data more meaningful and enhance its interpretability.

The discussion has improved; however, the results do not correlate with the discussion.

 

The sentences are vague and do not convey a message for the need to conduct this study. For example, "Over the last 10 years, it has been esteemed that the diagnosis of new cases and the number of patients 143 have increased by about 20 times". However, the authors do not report the incidence of the disease and are very vague in their sentences.

 

 

Comments on the Quality of English Language

Over the last 10 years, it has been esteemed that the diagnosis of new cases and the number of patients 143 have increased by about 20 times.

It could be rephrased as:  In the last ten years, the incidence of new cases (of which disease In Italy) has increased about 20 times. 

Esteemed should be estimated

 

 

Author Response

First of all, the authors would like to thank the editors and reviewers for their time and effort in addressing potential concerns on our manuscript.

Hereby, a point-by-point response for the reviewer 3 comments and suggestions:

 

Reviewer comment

1. One crucial aspect that needs further clarification is the participant assignment process. The authors have provided a detailed power calculation for the study (n=500), which is commendable.

Authors response

The authors would like to thank the reviewer for their insightful comments.

Reviewer comment

2. However, it remains unclear how the participants were assigned to the control group versus the treatment group, and what led to the discrepancies in the number of participants in each group.

Authors response

We added a specification: “Patients were asked to self-disclose a diagnosis of i) Chrohn’s disease; ii) Ulcerative Colitis; iii) Irritable Bowel Syndrome (IBS); iv) undergoing further testing before reaching a diagnosis; v) none of the above.”

Reviewer comment

3. The authors mention that “164 were in the control group” and the rest were in the treatment group. Understanding this process is vital as it directly impacts the validity of the study's results.

Authors response

Subjects were asked to self-disclose a diagnosis of IBS, IBD or whether they were awaiting for a formal diagnosis. We recruited patients through patients associations.

Reviewer comment

4. Another area that requires attention is the presentation of figures and tables. Currently, the figures lack an explanation of the axis, rendering them meaningless.

Authors response

We added the following legends.

For Figure 1 – Boxplot VSI-IT between groups

“Legend: The x-axis represents the total VSI-IT score (range 0-75); the y-axis represents the comparison groups, divided according to diagnosis (Healthy Controls; Crohn’s Disease; Ulcerative Colitis; Irritable Bowel Syndrome; Subject awaiting for a formal diagnosis).”

For Figure 2  – Boxplot of VSI-IT according to symptom severity

“Legend: The x-axis represents the total VSI-IT score (range 0-75); the y-axis represents the comparison groups, divided according to the symptoms severity (absent; mild; moderate; severe).”

Reviewer comment

5. Similarly, Table 3 does not convey any clear message, making it difficult to interpret. Recommend removing it.  

Authors response

In our view Table 3 is essential, since it provides specific statistical indices (descriptives), including mean, standard deviations, and confidence intervals, helping to know precisely each group scores. This information enables future comparisons, aiding clinicians in compare patient scores with groups means and SD and researchers in validating hypotheses and exploring new correlations. Furthermore, we clarified the table object and aim by editing the title. We hope now you (as all readers) can understand our purpose.

Reviewer comment

6. Providing clear titles and explanations will make the data more meaningful and enhance its interpretability.

Authors response

Yes, we agree. We changed the title of Table 3 – Sensitivity and validity of VSI-IT in discriminating between various pathological conditions In “Table 3 - Descriptives of VSI-IT in various pathological conditions”.

Reviewer comment

7. The discussion has improved; however, the results do not correlate with the discussion.

Authors response

The discussion has been completely revised, to enhance its coherence with respect to the results and findings were presented with a more structured order. We hope now you can agree that it’s improved, we are more satisfied, thank you for all suggestions.

Reviewer comment

8. The sentences are vague and do not convey a message for the need to conduct this study. For example, "Over the last 10 years, it has been esteemed that the diagnosis of new cases and the number of patients 143 have increased by about 20 times". However, the authors do not report the incidence of the disease and are very vague in their sentences.

Authors response

 We added specifications: “ On 2018, there were 15,141 prevalent IBD patients, corresponding to 442.3 per 100,000 inhabitants/year. The prevalence increased by approximately 10% annually from 2010, with projections for Italy estimating over 15,000 new cases/year [12].”

Reviewer comment

9. Comments on the Quality of English Language

Over the last 10 years, it has been esteemed that the diagnosis of new cases and the number of patients 143 have increased by about 20 times.It could be rephrased as:  In the last ten years, the incidence of new cases (of which disease In Italy) has increased about 20 times. 

Authors response

We rephrase the sentence, as you indicated, by changing “Over the last 10 years, it has been esteemed that the diagnosis of new cases and the number of patients have increased by about 20 times” into “In the last ten years, the incidence of new cases In Italy has increased about 20 times.”

Reviewer comment

10. Esteemed should be estimated

Authors response

We added a new reference with the estimated incidence in Italy: Crocetti, E., Bergamaschi, W., & Russo, A. G. (2021). Population-based incidence and prevalence of inflammatory bowel diseases in Milan (Northern Italy), and estimates for Italy. European Journal of Gastroenterology & Hepatology, 33(1S), e383-e389.

Thank you for your hard work and attention to the quality of our paper. We hope you could be satisfied with this new version of the paper.

 

Kind regards,

The corresponding Authors