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: 1 Date: 01 Dec 2018 
 
Reviewer:  HC Lien 
 
Reviewer’s report:  
 
comprehensive approach. They also emphasized th e limitations of data quality due to the nature 
of a retrospective study design.  
 
In general, I would consider that the data is valuable among Taiwanese patients with reflux 
esophagitis, in terms of exploring the etiology and developing future interventions .   
 
However, some important questions remain unanswered.  
 
1. First, being the major outcome or the sole dependent variable, reflux esophagitis was 
diagnosed in the majority (59.6%) of participants who underwent routine health check, 
which is extra -ordinari ly high. Second, the vast majority of reflux esophagitis was 
diagnosed as Los Angeles Classification Grade A, which is well known to have poor 
interobservers' agreement and may lead to the questionable prevalence rate. Third, non -
erosive reflux disease is believed to be more common than reflux esophagitis in Asian. 
Thus, the observation is likely due to overdiagnosis or misclassification. Overall, the 
possible misclassification may be a major thread to the validity of the study. Therefore it 
is recommended to evaluate the inter -observer agreement of the diagnosis of reflux 
esophagitis.  
 
2. The methods to define H. pylori infection and hiatal hernia should be described. In fact, 
the most epidemiological data from Asian countries including Taiwan showed a nega tive 
association between H. pylori and RE.   
 
3. The definition of alcohol consumption and smoking should also be described.  
 
4. In table 3 of the revised manuscript, elevated TG is significantly associated with RE after 
adjusting age and sex, whereas elevat ed TG was not associated with RE in the results and 
abstract. Would it be possible to explain the discrepancy between them?  
 
5. On page 18, line 13 'Second, the individuals with RE were not evenly distributed among 
the groups with LA grade A, B, and C. Bec ause our study is a cross -sectional study rather 
than a randomized controlled trial, bias may occur in the treatment of study population.' I 
do not think that the distribution of RE severity has anything to do with either a cross -
sectional study or randomi zed control trial.  
 
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.  
 
No 
 
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.  
 
Not relevant to this manuscript  
 
Quality of written English  
Please i ndicate the quality of language in the manuscript:  
 
Needs some language corrections before being published  
 
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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