Comfort and Support Values Provided by Different Pillow Materials for Individuals with Forward Head Posture
Round 1
Reviewer 1 Report
The paper refers to pillow design but there is not shown, but these pillows differ by material of stuffing, weight and size. Profile was not shown.
By defining the types of pillows and giving their dimensions, the capacity can be indicated at the same time, although the thickness dimension may be subject to change (especcially under preasure). Of course, the weight and type of material can in some way define the characteristics of the cushions.
The division of participants into FHP ≥3cm and FHP< 3cm has not been justified in any way. If to analyze the equality in FHP values should be accepted difference based on cluster analysis or justified value from literature.
First sentence of introduction: Most physical jobs are now undertaken by machines due to changes in lifestyle, seems incorrect and not poven at all. There is a number of jobs which is performed in sitting position which number can be given and there should be given a reference here.
In Table 3, it is unreasonable to give the area value in cm2 to two decimal places. This would also improve the readability of this table.
Units on 6 charts within Figure 2 are not given and Lateral comfort chart description if not fully visible.
General remarks on the paper is that this could be treated as a good example of research on the topic of sleep aids, but at this point not justify enough.
Author Response
Dear Editor
First of all, we would like to thank you and the reviewers for your comments and suggestions that will improve the quality of the research. Our article has been completely revised in line with your suggestions. The revised parts are explained one by one. The parts that cannot be corrected are explained in the limitation section.
Best regards,
Reviewer 1
The paper refers to pillow design but there is not shown, but these pillows differ by material of stuffing, weight and size. Profile was not shown.
R1. Dear reviewer, I can easily say that the main variable we investigated in our study was the pillow material. It would be more appropriate to use the word "material" as the word "design" in the title can be confusing.
(Page 1, Line 2)
By defining the types of pillows and giving their dimensions, the capacity can be indicated at the same time, although the thickness dimension may be subject to change (especcially under preasure). Of course, the weight and type of material can in some way define the characteristics of the cushions.
R2. The main theme of the study was arranged as "pillow material". Other minor differences, such as weight and size, were not investigated in this study, as they were due to changes in the inner material of the pillow.
The division of participants into FHP ≥3cm and FHP< 3cm has not been justified in any way. If to analyze the equality in FHP values should be accepted difference based on cluster analysis or justified value from literature.
R3. Dear reviewer. We agree with your views on the justification. Based on our clinical experience, we accepted values of 2.5-3 cm and below as “Slight FHP”. We know that there are many studies in the literature that use median values to create two different groups. Since the median value is very close to 3 cm, we accepted this value as a reference. However, we understand that we need to base this value on the literature. In our research, we noticed that the median value of 3 cm is close to the reference value for "Slight FHP" and "Mild upper cross syndrome" (1-2.5 cm). We have added the relevant literature to the method section. Since there are no participants between 2.8-3 cm, we can make this change (2.8cm) without affecting our statistical analysis. Thus, we brought our median value closer to the reference value in the literature. Thanks for your attention.
(Page 4, Line 223-226)
First sentence of introduction: Most physical jobs are now undertaken by machines due to changes in lifestyle, seems incorrect and not poven at all. There is a number of jobs which is performed in sitting position which number can be given and there should be given a reference here.
R4. In line with your suggestions, the first paragraph has been completely revised. Three new references have been added to the relevant sections.
(Page 1, Line 29-36)
In Table 3, it is unreasonable to give the area value in cm2 to two decimal places. This would also improve the readability of this table.
R5. The changes you requested have been made in Table 3 and Table 4.
(Page 7-8)
Units on 6 charts within Figure 2 are not given and Lateral comfort chart description if not fully visible.
R6. Dear reviewer, we have explained the units of both comfort and support values at the bottom of the table. However, if there is anything else that we misunderstood and needs to be corrected, please let us know. We are sorry that we do not fully understand.
General remarks on the paper is that this could be treated as a good example of research on the topic of sleep aids, but at this point not justify enough.
Thank you for your careful review. Regards,
Reviewer 2 Report
- Abstract. Ln 8-10. The authors mentioned that “based on the pressure distribution in the head, neck, and upper body and the spine support values, this study aims to recommend the most suitable pillow for those with forward head posture (FHP) according to different sleeping positions” (also can be seem at Ln. 133-137). The relationship between the selected measures and factors still unclear. Please address this issue more specific. Moreover, there are many different pillow designs, why the five pillows were used?
- Ln-29-31, 31-33 References need to be cited here.
- Ln 39-41 “While studies on the support and comfort of human contact surfaces generally focus on sitting posture, there is limited information available because the assessment of sleep position is more complex”. In fact, there are many studies have been focused on the contact surfaces (pressures) in sleeping position. The following references are given as example and please consider to use in the manuscript. Thus, the reasons to conduct this study are insufficient.
l Better combination of thickness and hardness of mattress topper for supine sleeping posture: A physiological measurements evaluation
l Effects of mattress material on body pressure profiles in different sleeping postures.
l Effects of interface pressure distribution on human sleep quality.
l Ergonomic consideration in pillow height eterminants and evaluation
l Effects of Body Pillow Use on Sleeping Posture and Sleep Architecture in Healthy Young Adults
4. Ln 150-151. Redundancy sentences.
5. Why divide the participants into mild and severe FHP groups? There is no clear reason to support.
6. Why limit the participants who with a body mass index of less than 30 kg/m2?
7. From Ln 156 to Table 1. The selected five pillows are not clearly described. From the Table 1, seems that the major different parameter is material. However, the feature of pillow A seems very differ to the others, such as size, fabric type, and stuffing. These became one of the major issues.
8. From Ln 147-153. A picture to explain how to calculate the FHP will be suggested.
9. There is no information about the other important features that you mentioned in the Introduction for influencing the subjective comfort determination. For example, the hardness, firmness, shape…). Please classify.
10. It will be good if the authors can provide the clear picture of the selected five pillows and attached in Table 1, as well as the mattress.
11. Ln 167 Here has a gramma problem.
12. Ln 169-171 A illustration for demonstrating the reference points could be useful for enhancing the readability.
13. Ln 187-189. Lower pressure value has used to represent “higher comfort”. What is the lower pressure mean? Average pressure? Or the lower pick pressure?
14. Subsequently, authors used lower pressure and more contact area to represent better comfort and support, respectively. Does any reference use the same criteria? I thought that the two measures have strongly interaction.
15. Why not the pressure system positioned “under” the pillow? (the authors mentioned that placed “on” the pillow)
16. For the results section, three-way ANOVA analysis (FHP group, posture and pillow type) was strongly recommended. This can extract more interesting findings.
17. LN 327-328. From Table 1, the range of height is 10 -19 cm. This is not so called “almost the same height”.
18. For limitation, different firmness and hardness of mattress has impacted to whole body pressure. In the current study, a medium-firm hybrid mattress was used. This should be pointed out as the limitation.
19. The quality of all figures should be improved, especially in Figure 2.
20. LN 201-202 “Participants tried the pillows first in the supine position, then side-lying, and finally in the prone position.” It indicated that the test order was not randomly assigned. Why?
Author Response
All changes in the second round are highlighted in green.
- Abstract. Ln 8-10. The authors mentioned that “based on the pressure distribution in the head, neck, and upper body and the spine support values, this study aims to recommend the most suitable pillow for those with forward head posture (FHP) according to different sleeping positions” (also can be seem at Ln. 133-137). The relationship between the selected measures and factors still unclear. Please address this issue more specific. Moreover, there are many different pillow designs, why the five pillows were used?
R1. Abstract. Ln 14-17.
Dear reviewer, Based on your comment, we noticed that we did not include our main outcome measure in the summary. In this way, the relevant section could be explained more specifically. In addition, the word design had a very comprehensive and assertive meaning. For this reason, we used the word “material” instead of the word “design”. On the other hand, we evaluated five different materials that are mainly preferred in pillow production. We applied the relevant word change to all parts of our article. Thank you for your contribution.
2. Ln-29-31, 31-33 References need to be cited here.
R2. Line 30: The relevant part has been removed in the previous revision round directive.
3. Ln 39-41 “While studies on the support and comfort of human contact surfaces generally focus on sitting posture, there is limited information available because the assessment of sleep position is more complex”. In fact, there are many studies have been focused on the contact surfaces (pressures) in sleeping position. The following references are given as example and please consider to use in the manuscript. Thus, the reasons to conduct this study are insufficient.
l Better combination of thickness and hardness of mattress topper for supine sleeping posture: A physiological measurements evaluation
l Effects of mattress material on body pressure profiles in different sleeping postures.
l Effects of interface pressure distribution on human sleep quality.
l Ergonomic consideration in pillow height eterminants and evaluatio
l Effects of Body Pillow Use on Sleeping Posture and Sleep Architecture in Healthy Young Adults
R3. Line 42-99: Thank you for this contribution. The studies you mentioned are included in the introduction and relevant references have been added.
- Ln 150-151. Redundancy sentences.
R4. Line 266: We have removed the mentioned sentence.
- Why divide the participants into mild and severe FHP groups? There is no clear reason to support.
R5. (Line 266-270) We made the group distinction to show that posture changes can be effective in the selection of pillow material. In the previous review round, we justified how we made this distinction.
- Why limit the participants who with a body mass index of less than 30 kg/m2?
R6. Before starting the research, we received training on material selection from a professional materials engineer. The mattress we used was a hybrid mattress produced within the scope of the 5-zone package spring system. It was stated that spring quality is not suitable for individuals with a body mass index over 30 kg/m2. We made such a decision so that the mattress variable would not affect the results.
- From Ln 156 to Table 1. The selected five pillows are not clearly described. From the Table 1, seems that the major different parameter is material. However, the feature of pillow A seems very differ to the others, such as size, fabric type, and stuffing. These became one of the major issues.
R7. We agree with your opinion. However, pillow A is considered an innovative pillow due to its design and material. Other pillows are classified as "conventional". We talked about this distinction in the Discussion section. We agree with the idea that the key variable is material, and we've corrected this misunderstanding throughout our article.
- From Ln 147-153. A picture to explain how to calculate the FHP will be suggested.
R8. Line 282: We have added a picture for easier understanding of the method.
- There is no information about the other important features that you mentioned in the Introduction for influencing the subjective comfort determination. For example, the hardness, firmness, shape…). Please classify.
R9. Subjective comfort was not investigated in our study. It will be included in outcome measures in future studies. In addition, in line with both your suggestions and the suggestions of the referees in the first round, the main theme of our research was limited to material research.
- It will be good if the authors can provide the clear picture of the selected five pillows and attached in Table 1, as well as the mattress.
R10. Line 301: We have added the pictures you want to our manuscript.
- Ln 167 Here has a gramma problem.
R11. Fixed grammatical errors in the mentioned sentence.
“The participants’ posture was analyzed using a high-resolution camera positioned 1.5 meters away”.
- Ln 169-171 A illustration for demonstrating the reference points could be useful for enhancing the readability.
R12. In Figure 1, we have specified the relevant reference points.
- Ln 187-189. Lower pressure value has used to represent “higher comfort”. What is the lower pressure mean? Average pressure? Or the lower pick pressure?
R13. The sentence you mentioned was edited as follows:
Line 342-345: A lower average pressure measured by the device was defined as indicating "higher comfort", while greater contact between the head area and the pillow was considered to indicate "better support"
- Subsequently, authors used lower pressure and more contact area to represent better comfort and support, respectively. Does any reference use the same criteria? I thought that the two measures have strongly interaction.
R14. These measurements are mostly used in commercial research. You can check the link below for relevant references:
https://www.xsensor.com/solutions-and-platform/sleep-improvement/mattress-design-r-d
- Why not the pressure system positioned “under” the pillow? (the authors mentioned that placed “on” the pillow)
R15. Line 338: We realized that we made a grammatical error. We have made corrections where relevant. Thank you for your attention.
- For the results section, three-way ANOVA analysis (FHP group, posture and pillow type) was strongly recommended. This can extract more interesting findings.
R16. We totally agree with your comment. However, our data were not normally distributed and we hypothesized that dividing the groups into two would dramatically increase the Type 1 Error rates of the ANOVA results. In order not to mislead readers, we have chosen simpler analyzes. Our research on the subject continues and the number of our sample is increasing day by day. Your suggestion will certainly be taken into account in our further research.
- LN 327-328. From Table 1, the range of height is 10 -19 cm. This is not so called “almost the same height”.
R17. Line 1128-1131: Due to its viscoelastic structure, the relevant pillow remained at a similar height to conventional pillows under pressure. However, we still included it in our research limitations.
- For limitation, different firmness and hardness of mattress has impacted to whole body pressure. In the current study, a medium-firm hybrid mattress was used. This should be pointed out as the limitation.
Line 1128-1129: We've added the limitation you suggested.
- The quality of all figures should be improved, especially in Figure 2.
R19. Line 974: We improved the image quality of Figure 2 (Renamed Figure 4.)
- LN 201-202 “Participants tried the pillows first in the supine position, then side-lying, and finally in the prone position.” It indicated that the test order was not randomly assigned. Why?
R20. Since the results were not compared with each other, we believed that regular application would not introduce bias.
Thank you for your unique contributions. Kind regards,
Author Response File: 
Author Response.docx
Reviewer 3 Report
The paper is well written and very careful in its presentation.
The introduction is more than satisfactory, the references are relevant to the text. The design looks neat. I liked the idea and think it is original.
The figures are very informative.
Βut I would like some clarification.
The similarity of the pillows was tested before the research on the pressure and disconford they exert? Would this change the results of the survey?
The admission criteria are not clear. If the patient suffered, for example, from respiratory diseases or ear diseases, did not this fact affect the study?
Although the limitations are clear, how can they complete Pittsburgh's sleep quality if they don't sleep?
How has IPAQ helped you research?
Author Response
Dear Editor
First of all, we would like to thank you and the reviewers for your comments and suggestions that will improve the quality of the research. Our article has been completely revised in line with your suggestions. The revised parts are explained one by one. The parts that cannot be corrected are explained in the limitation section.
Reviewer 2
The paper is well written and very careful in its presentation.
The introduction is more than satisfactory, the references are relevant to the text. The design looks neat. I liked the idea and think it is original. The figures are very informative. Βut I would like some clarification.
- The similarity of the pillows was tested before the research on the pressure and disconford they exert? Would this change the results of the survey?
R1. In our study, all pillows except Visco went through a similar production process. Visco pillow production is designed in accordance with its own standards. We took care to design the pillows used in the research in such a way that only the material changes. Small differences in weight and size are due to the density of the material itself. We think that the possible pressure (comfort) or support (area) changes that will occur here will mostly depend on the material (Visco, Cotton, Wool etc.) from which the pillow is produced.
- The admission criteria are not clear. If the patient suffered, for example, from respiratory diseases or ear diseases, did not this fact affect the study?
R2. We previously determined the exclusion criteria of the patients.
“Exclusion criteria included a history of neck pain, carpal tunnel syndrome, a shoulder joint lesion in the past three months, cervical spine trauma, inflammatory or viral illnesses of the spine, spinal surgery, or congenital spinal deformities.”
(Page 3, Line 202-205)
However, we realized that the additional criteria you mentioned may also affect the results of the study. Unfortunately, we did not query this information. We have stated the relevant deficiencies in the limitation section.
“Although the exclusion criteria of our study were strictly defined, the participants were not questioned about ear diseases or respiratory problems. Failure to evaluate these problems, which may affect body posture and sleep habits, is an important limitation of our study.”
(Page 12, Line 1003-1006)
- Although the limitations are clear, how can they complete Pittsburgh's sleep quality if they don't sleep?
R3. Sleep quality measurements were made prior to pillow analyses, only to standardize them. More detailed explanation on the subject is given in the next question.
(Page 4, Line 230-233)
- How has IPAQ helped you research?
R4. One of the factors affecting sleep habits is considered to be the level of physical activity. Therefore, there was a need to demonstrate that the level of physical activity among the participants was similar in our study. The relevant explanation has been added to the methods section. Thank you for your contribution.
“The Pittsburgh Sleep Quality Index was used to measure the current sleep quality of the participants, and the International Physical Activity Questionnaire was used to measure the level of physical activity, which is one of the possible factors that can change their sleep habits.”
Round 2
Reviewer 1 Report
Thank you for addressing the comments. The article in this form is clearer. The rather small weight of the subjects may be a certain limitation of the study conducted, it may be worth mentioning this in the limitations of the study.
Author Response
R1. Dear reviewer,
First of all, we are grateful for your unique contribution to our work.
Line 1126: It is stated in the first sentence of the "limitation" section that the study should have a larger sample size.
Reviewer 2 Report
No more critical questions from my opinion. It can be take into consideration for accepting in the current for.
One minor comments, the styles of the reference list are not the same. The authors need to watch out this minor issue in the proofreading stage.
