Review for 10.1186/s12876-018-0832-9 (2018)

Reviewer ’s report  
 
Title: Gastroesophageal reflux symptoms among Italia n university students: epidemiology and 
dietary correlates using automatically recorded transactions  
 
Version: 2 Date: 24 Apr 2018  
 
Reviewer: Ammar Hassanzadeh Keshteli  
 
Reviewer's report:  
 
I read with interest Martinucci et al.'s manuscript which presents results of a cross -sectional 
study among university students on the relationship between several lifestyle related factors and 
gastroesophageal reflux disease. The topic of the project is important as GERD is highly 
prevalent and there should be further investigations to identify its lifestyle -related risk factors. I 
have some concerns though:  
1) Since there has been no face -to-face assessment by a physician or no endoscopic evaluation, 
I am wondering if using the term "gastroesophageal reflux disease" is appropriate. One may 
think that in this case, using uninvestigated heartburn/regurgitatio n/ gastroesophageal reflux 
should be more relevant.  
 
2) Please mention how you defined "GERD in this study. Did you also assess the severity of 
symptoms?  
 
3) Have the authors validated their questionnaires that was used through the app/website? If 
not, this should be mentioned in their limitation paragraph  
 
4) Have the authors validated dietary intake information collected by DSU using more valid 
tools such a s dietary records, recalls, or food frequency questionnaires? Can the authors 
clarify what percentage of total caloric intake of participants per day came from foods 
purchased at DSU? There is major concern that the dietary intake information collected by 
DSU usage, is not reflective of participants habitual dietary intake.  
 
5) Has there been any validation study for self -reported anthropometric measurements?  
 
6) How did you assess smoking habits? Did you mean "current smoker" by "Yes" in Table 2? 
Please clar ify. 
 
7) Definition of BMI categories should be included in the methods section (or in Table 1).  
 
8) Titles for Table 1, 2, and 4 are not informative. Please revise.  
 
9) Please provide P values for the comparison between males and females in Table 1.  
 
10) In Table 2, it is not clear what the authors mean by "groups" in the "P -value <0.05 for 
comparison between groups". Please clarify.  
 
11) For the comparisons of categorical variables (e.g. gender) between GERD vs no -GERD 
participants, please also report odds ratios and 95% confidence intervals.  
 
12) There is a major concern regarding statistical analysis: Currently, your conclusions are 
solely based on simple univariate analysis which is not correct. You must perform 
multivariate regression analysis in order t o report adjusted ORs and p values.  
 
13) What did you mean by "True" and "False" in Table 4?  
 
14) In Tables 2 and 4, please mention the unit for coffee consumption  
 
15) How did you define "frequent users"?  
 
16) If a person was not frequent user, why did you s till include their information for statistical 
analysis?  
 
17) Was there any difference between users and non -users in terms of GERD prevalence?  
 
18) In Table 5, what is the unit for frequency of foods consumption?  
 
19) Since multivariate analysis has not been  performed in this study and there is a huge concern 
that dietary intake information in this study is not reflective of participants actual dietary 
intake, it is difficult to speculate the observed relationship between higher rice and pasta 
consumption and  lower prevalence of "GERD". However, this finding should be discussed 
in more details. There has been a recent publication on the relationship between quality of 
carbohydrate intake and upper gastrointestinal disorders (PMID: 28634998).   
Are the methods appropriate and well described?  
If not, please specify what is r equired 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.  
 
No 
Are the conclusions drawn adequately supported by the data shown?  
If not, pleas e 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.  
 
I am able to assess the statistics  
 
Quality of written English  
Please indicate 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, funding, or salary from an  
organisation that may in any way gain or lose financially from the publicat ion 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 the publication of this manuscript, either now or in the future?  
 
3. Do you hold or are you current ly 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 ot her 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 giv e details below.  
 
I declare that I have no competing interests.  
 
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