Sleep Quality, Pain, Worry, and Rumination in Fibromyalgia: Results from Mediation Analyses

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Tenti and colleagues presented “Sleep Quality, Pain, Worry, and Rumination in Fibromyalgia: Results from Mediation Analyses,” a study that utilized telephone assessments of 734 individuals with fibromyalgia. The authors analyzed how sleep quality, worry, and depressive rumination related to pain intensity. Authors should specify whether observed correlations are weak, moderate, or strong, so readers can understand the significance of the results. The authors concluded that sleep quality was linked to pain in fibromyalgia and was affected by depressive rumination and worry. They should clarify that these symptoms may reflect hormonal, neurochemical, and inflammatory changes.

Author Response

Responses to Reviewer 1

1. Tenti and colleagues presented “Sleep Quality, Pain, Worry, and Rumination in Fibromyalgia: Results from Mediation Analyses,” a study that utilized telephone assessments of 734 individuals with fibromyalgia. The authors analyzed how sleep quality, worry, and depressive rumination related to pain intensity. Authors should specify whether observed correlations are weak, moderate, or strong, so readers can understand the significance of the results.

ANSWER: Following your suggestion, we have specified the strength of the observed correlations. For the interpretation of correlation magnitudes, we used the guidelines proposed by Gignac and Szodorai (2016), according to which correlations of 0.10, 0.20, and 0.30 can be considered relatively small, typical, and relatively large, respectively. We have also updated the Methods and Results sections to comment on the strength of each correlation.

2. The authors concluded that sleep quality was linked to pain in fibromyalgia and was affected by depressive rumination and worry. They should clarify that these symptoms may reflect hormonal, neurochemical, and inflammatory changes.

ANSWER: We have revised the discussion to clarify that sleep disturbances and pain may also be affected by biological mechanisms such as hormonal, neurochemical, and inflammatory changes, which could further contribute to the complexity of these symptoms in FM. The new sentence has been included in the “Discussion” (specifically, at the end of the paragraph concerning the limitations of the study).

Reviewer 2 Report

Comments and Suggestions for Authors

Please see attached file.

Comments for author File: Comments.pdf

Author Response

Responses to Reviewer 2

1. The below constitutes a review of the manuscript entitled ‘Sleep Quality, Pain, Worry, and Rumination in Fibromyalgia: Results from Mediation Analyses’.  The aims of the study were to determine whether sleep disturbances mediate the relationship between the following:  1).  worry and pain intensity, and 2).  depressive rumination and pain intensity in adults who had been diagnosed with fibromyalgia (FM).  The main strength of this study is that it adds to the base of published literature in that no published study has examined the mediating role of sleep disturbances in the association between forms of Repetitive Negative Thinking (RNT).  Another pro to this investigation is the relatively large sample size (as well as response rate), as this study consisted of an online, cross-sectional survey. General Concept Comments: In general, I believe this manuscript is very well written and will be a good addition to the published literature.  I thank the authors for all the time and attention not only for conducting this study, but in preparing this manuscript! I enjoyed reading. Basically, my suggestions have to do with enhancing the clarity of this manuscript. 

ANSWER: Thank you very much for your thoughtful and encouraging feedback. In response to your comments, we have focused on improving the clarity of the Methods and Results sections, as suggested in points 2 and 3, to make the presentation of our findings more concise and reader-friendly.

2. Specific Comments: Abstract – Clear, concise. I have no suggestions for improvement. Introduction – The introduction is well written. It makes a strong case for the study and the study objectives. Again, it is clearly written and explains how this study will fill a gap in the published literature. Very nice!

Materials and Methods – I appreciate how you took the time to describe each of the measures. Even a reader who is not familiar with these measurements will come away with a good understanding based on your explanations.  Thank you. 

One suggestion I would like to make is to include the ranges for each of the instruments.  For example, the Italian version of the Penn State Worry Questionnaire (PSWQ) you could include this (in line 146) as follows: ‘Higher scores (Range xx – xx)  indicate greater levels of worry.’  I would consider doing this for each measurement.  I realize you have provided enough information that the reader could calculate the range, but I would consider making it easy on the reader so he/she doesn’t have to stop reading and do the calculation.  Otherwise, the Materials and Methods section are very nicely done.   

ANSWER: As suggested, we have included the score ranges for the Italian version of the Penn State Worry Questionnaire (PSWQ) and the Ruminative Response Scale to make it easier for readers to interpret the results. The range for the Pittsburgh Sleep Quality Index (PSQI) was already reported in the original manuscript.

Additionally, we have clarified how the total pain intensity score was calculated and explicitly reported the possible score range for this measure.

3. Results - The first two paragraphs are great and I appreciate the details of the sample and response rate! For the sake of clarity, I would keep the first sentence of paragraph three (line 209) beginning ‘Table 1 presents………’.  Then I would add the rest of the results to Table 1 instead of including verbiage regarding the results for these demographic variables. For example, ‘age’ is already included in Table 1, but please add unit of measurement (years) and also the range (18-76 years) to the Table.  Then please add the mean + sd years FM patients had been living with chronic pain (and the range), mean + sd years from symptom onset to diagnosis (and the range), and then N(%) or N (78%) of participants reported taking medication or undergoing treatment.  Also, for ‘Pain duration’ (already listed in Table 1) please add units of measurement (years) and range.  The idea here is the following:  1).  Tables should always be stand alone.  Meaning they should always include units of measurement (even when it is basically ‘common sense’), and 2).  Including the Range just helps the reader understand the data better, and 3).  Most of the time authors don’t tend to include verbiage regarding demographic information and include it in a Table.  If you can concisely arrange it in a table it makes the readers job so much easier, in my opinion. The rest of the results are clear and very nicely presented!          

ANSWER: In line with your feedback, we have removed the descriptive text from the Results section and integrated all the relevant data into Table 1, including units of measurement for each variable.

Please note, however, that the variable previously described as “years FM patients had been living with chronic pain” corresponds to pain duration, which was already included in the table. For this variable, we have now added the range as requested.

Regarding the “years from symptom onset to diagnosis,” it was not possible to include a range because this variable was assessed using categorical response options rather than an open numerical response. The response categories are already reported in Table 1.

We hope this revision meets your expectations and provides greater clarity for the readers.

4. Discussion – This section is nicely done. The discussion is well written, future research is included, the limitations are explained in depth, clinical implications/ interventions are nicely thought out, and the conclusion is clearly stated. Overall, nicely done-thank you! 

ANSWER: Thank you very much for your kind feedback. We greatly appreciate your positive evaluation of our work.

Reviewer 3 Report

Comments and Suggestions for Authors

The manuscript addresses an important and under-explored question in fibromyalgia research: the mediating role of sleep disturbances in the relationship between repetitive negative thinking (worry and rumination) and pain intensity. The introduction is thorough and provides a strong rationale. The methodology is sound, with validated instruments and robust statistical analyses, though the reliance on online recruitment via a patient association introduces possible selection bias. The results are clearly presented, and the discussion thoughtfully connects findings to existing literature, highlighting clinical implications and limitations.

I recommend moderate language editing and a more explicit discussion of the limitations (sample representativeness, variance explained, exclusion of PSQI item, potential response bias). Expanding the clinical implications, especially regarding interventions for rumination and worry in fibromyalgia, would further strengthen the paper.

Comments on the Quality of English Language

The manuscript is understandable and conveys the scientific message clearly, but the English could benefit from editing to improve clarity and flow. Sentences are sometimes unnecessarily long or complex. Simplifying structure, avoiding redundancy, and polishing grammar would make the paper more accessible to an international readership.

For example:

• “Despite evidence of interrelationships among these factors…” → could be simplified to “Although previous studies have shown links among these factors…”

• “Experimental studies indicate that sleep deprivation can induce FM-like symptoms…” → could be simplified to “Experimental studies show that sleep deprivation can induce FM-like symptoms…”

• “This is not be surprising, as pain in FM is a complex construct…” → should be “This is not surprising, since pain in FM is a complex construct…”

These are minor adjustments, but systematic editing of this kind throughout the manuscript will improve readability.

Author Response

Responses to Reviewer 3

1. The manuscript addresses an important and under-explored question in fibromyalgia research: the mediating role of sleep disturbances in the relationship between repetitive negative thinking (worry and rumination) and pain intensity. The introduction is thorough and provides a strong rationale. The methodology is sound, with validated instruments and robust statistical analyses, though the reliance on online recruitment via a patient association introduces possible selection bias. The results are clearly presented, and the discussion thoughtfully connects findings to existing literature, highlighting clinical implications and limitations.

ANSWER: Thank you for your constructive feedback. We appreciate your point regarding the potential selection bias related to online recruitment. While we had already acknowledged the possibility of self-selection bias in the original manuscript, we have now expanded this section to more broadly discuss the limitations associated with online data collection. Specifically, we now address the exclusion of individuals without Internet access or limited digital literacy, and the potential overrepresentation of highly motivated participants. These revisions have been added to the Limitations section to clarify this issue.

2. I recommend moderate language editing and a more explicit discussion of the limitations (sample representativeness, variance explained, exclusion of PSQI item, potential response bias).

ANSWER: Thank you for your helpful feedback. We have carefully revised the Limitations section to address the points you raised. Specifically, we have:

1. Moderated the language throughout the section to improve readability and clarity.
2. Expanded our discussion of sample representativeness, explicitly addressing selection bias and response bias due to online recruitment and differences between respondents and non-respondents.
3. Clarified the rationale for the exclusion of one PSQI item, noting its impact on internal consistency and comparability.
4. Provided a more explicit discussion of the variance explained by the models, emphasizing that other biopsychosocial factors likely play a role in FM pain.

We hope these revisions adequately address your concerns and improve the clarity and completeness of our discussion.

3. Expanding the clinical implications, especially regarding interventions for rumination and worry in fibromyalgia, would further strengthen the paper.

ANSWER: We thank the reviewer for this helpful suggestion. In the revised manuscript, we have expanded the discussion of potential clinical interventions by providing a more detailed description of Metacognitive Therapy (MCT) and Rumination-Focused Cognitive-Behavioral Therapy (RF-CBT). Specifically, we explain how MCT targets dysfunctional metacognitive beliefs and helps individuals disengage attention from intrusive thoughts, while RF-CBT focuses on modifying unhelpful ruminative thinking styles. We have also included evidence supporting the efficacy of MCT for emotional disorders and clarified that, although neither approach has been tested in fibromyalgia populations, their theoretical frameworks align with the cognitive mechanisms identified in our study (see lines 318–402).

 

4. The manuscript is understandable and conveys the scientific message clearly, but the English could benefit from editing to improve clarity and flow. Sentences are sometimes unnecessarily long or complex. Simplifying structure, avoiding redundancy, and polishing grammar would make the paper more accessible to an international readership.

For example:

“Despite evidence of interrelationships among these factors…” → could be simplified to “Although previous studies have shown links among these factors…”

“Experimental studies indicate that sleep deprivation can induce FM-like symptoms…” → could be simplified to “Experimental studies show that sleep deprivation can induce FM-like symptoms…”

“This is not be surprising, as pain in FM is a complex construct…” → should be “This is not surprising, since pain in FM is a complex construct…”

These are minor adjustments, but systematic editing of this kind throughout the manuscript will improve readability.

ANSWER: Following your suggestion, we have carefully revised the manuscript to improve clarity and readability. Specifically, we addressed the specific examples you mentioned and simplified sentence structures, reduced redundancy, and polished the grammar throughout the text.