Review for 10.1186/s12876-019-0950-z (2019)

Reviewer ’s report  
 
Title:  What is the impact of metabolic syndrome and its components on reflux esophagitis? A 
cross -sectional study  
 
Version: 0 Date: 01 Oct 2018 
 
Reviewer:  Eivind  Ness -Jensen  
 
Reviewer’s report:  
 
This was a well written study on the association between the metabolic syndrom and its 
components and reflux esophagitis. I have the following comments:  
 
- The methods of the abstract should include more details about the methods used. How was the 
variables as sessed? Which statistical methods were used?  
 
- In the introduction, excess gastric acid is included in the list of the multifactorial process of RE. 
However, this is rare and should probably not be listed here.  
 
- HP-infections are usually reported as negat ively associated with GERD/RE, not positively as 
stated in the introduction.  
 
- In the introduction, the authors refer to a Chines retrospective case -control study claiming 
causality (ref 24). This should be corrected to "associations", as causation cannot be claimed in 
such a study.  
 
- The methods section should include a description of how the included variables from the 
questionnaires were assessed. What was the questions and response alternatives?  
 
- The discussion should include that the medical history w as self -reported and thus could 
introduce misclassification.  
 
- Excellent objective assessment of the antropometric factors.  
 
- I disagree with the use of statistical inference using p -values comparing baseline variables as in 
Table 1.  
 
- In the text of the r esults, the focus is on the univariate results, but should be on the adjusted 
multivariate results. The univariate results could be reduced and the multivariate increased.  
 
- I do not understand why the multivariate results are separated in two tables. They  should be 
presented in one table of the main multivariable results, including all the relevant variables.  
 
- Why did the authors adjust for BMI only and not WC only, as WC is probably the stronger risk 
factor of the two?  
- In the presentation of the result s it is not possible to understand which variables are compared 
to each other. What is the reference value? This should be explained in the methods section, as 
commented above.  
 
- The discussion is a very nice discussion of the different factors involved an d the strengths and 
limitations of the study, except missing a discussion of the problem with self -reported medical 
history.  
 
- In the discussion, calcium channel blockers are stated as important "causative factors". I believe 
this should be "associated fac tors".  
 
- In tables 2 -4 it is hard to understand what is the outcome and what is the comparison. This 
would have been easier to understand if the variables where better reported in the methods 
section. The tables should also state what the analyses are adju sted for? Adjusted for all the other 
variables?  
 
- Figure 2 is very nice and illustrative  
 
Are the methods appropriate and well described?  
If not, please specify what is required in your comments to the authors.  
 
No 
 
Does the work include the necessary controls?  
If not, please specify which controls are required in your comments to the authors.  
 
Yes 
 
Are the conclusions drawn adequately supported by the data shown?  
If not, please explain in your comments to the authors.  
 
Yes 
 
Are you able to assess any statistics in the manuscript or would you recommend an 
additional statistical review?  
If an additional statistical review is recommended, please specify what aspects require further 
assessment in your comments to the editors.  
 
I am able to assess the statistics  
 
Quality of written English  
Please i ndicate the quality of language in the manuscript:  
 
Acceptable  
 
Declaration of competing interests  
Please complete a declaration of competing interests, considering the following questions:  
 
1. Have you in the past five years received reimbursements, fees, fun ding, or salary from an 
organisation that may in any way gain or lose financially from the publication of this 
manuscript, either now or in the future?  
 
2. Do you hold any stocks or shares in an organisation that may in any way gain or lose 
financially from t he publication of this manuscript, either now or in the future?  
 
3. Do you hold or are you currently applying for any patents relating to the content of the 
manuscript?  
 
4. Have you received reimbursements, fees, funding, or salary from an organization that 
holds or has applied for patents relating to the content of the manuscript?  
 
5. Do you have any other financial competing interests?  
 
6. Do you have any non -financial competing interests in relation to this paper?  
 
If you can answer no to all of the  above, write 'I declare that I have no competing interests' 
below. If your reply is yes to any, please give details below.  
 
I declare that I have no competing interests  
 
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