Review for 10.1186/s12876-020-01417-6 (2020)

Reviewer ’s report  
 
Title: Epidemiology of Gastroesophageal Reflux Disease in Iran : A Systematic Review and Meta -
analysis  
 
Version: 0 Date: 23 Apr 2020  
 
Reviewer: Naoki Hashimoto  
 
Reviewer's report:  
 
Esophageal cancer is the 7th most common cancer in Iran  and it also is among the ten most 
common cancers in the world. Iran is a well -known region with a high prevalence for this cancer, 
mostly from the North and North East of the country. S moking tobacco and drinking of alcohol 
are strongly associated with SCC and to a lesser degree with adenocarcinoma of esophagus. 
Fortunately in Iran due to religious beliefs alcohol consumption is not popular, but smoking and 
drug abuse are most probably i mportant factors.  Author concluded that this study showed a high 
prevalence of GERD in Iran.  
 
I ask some question to author.  
 
1. Please tell me the etiology in GERD in Iran.  
 
2. Obesity and tobacco are harmful factor for GERD. Which is more harmful factor in  Iran?  
 
3. The GERD questionnaire is simple and straightforward. But I think Bilitec and PH meter 
are good tool to diagnosis of GERD. Please comment about Bilitec and PH meter.  
 
4. Iran is a well -known region with a high prevalence for this cancer, mostly fr om the North 
and North East of the country. Please tell me the reason why north east of Iran is very popular for 
SCC.  
 
Are the met hods appropriate and well described?  
If not, please specify what is required in your comments to the authors.  
 
Yes 
 
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 manus cript or would you recommend an additional 
statistical review?  
If an additional statistical review is recommended, please speci fy what aspects require further 
assessment in your comments to the editors.  
 
I am able to assess the statistics  
 
Quality of written English  
Please indicate the quality of language in the manuscr ipt: 
 
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, f ees, funding, or salary from an 
organisation that may  in any way gain or lose financial ly from the publication of this 
manuscript, either now or in the future?  
 
2. Do you hold any stocks or shares in an organisation t hat may in any way gain or lose 
financially from the 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 in terests' below.  
If your reply is yes to any, please give details below.  
 
'I declare that I have no competing interests' .  
 
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on my report to the authors and, if t he manuscript is accepted f or publication, my named report 
including any attachments I upload will be posted on the website along with the authors' responses. 
I agree for my report to be made available under an Open Access Creative Commons CC-BY 
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not wish to be included in my named report can be in cluded as confidential comments to the 
editors, which will not be published.  
 
I agree to the open peer review policy o f the journal