Review for 10.1186/s12876-018-0749-3 (2018)

Reviewer ’s report  
 
Title: Epidemiology of gastrointestinal symptoms in young and middle -aged Swiss adults:  
prevalences and comorbidities in a longitudinal population cohort over 28 years  
 
Version: 1 Date: 08 Dec 2017  
 
Reviewer: Mohammad Bashashati  
 
Reviewer's report:  
 
This is an interesting article; the findings are expected, if nobody has published similar data on 
this database, this would be suitable for publication.  
 
 
1) What questionnaire did you use for GI symptoms? Was it valid? Have you ever published 
GI data from this cohort? Why Stomach and intestine symptoms and not uppe r/lower GI 
symptoms.  
 
 
2) Whenever you report OR (you should include CI).  
 
 
3) the abstract has values and abbreviations which need definition or CI or SEM/SD.  
 
 
4) The manuscript needs technical revision, e.g. instead of saying "subacute>=1 week", you 
should say "1week <=subacute<=1 month. How did you come with idea of More than 1 
week as subacute; i.e. in diarrhea >2 weeks and <1 month is subacute  
 
 
5) "In order to increase the probability of the development of psychiatric syndromes, from 
this screening sample of 4547 persons a stratified subsample of 591 subjects (292 men, 
299 women) was selected for interview?" Development or detection? How did you select 
the sample size; any missing data? why? The methodology section is not clear.  
 
 
6) English needs revision.  
 
 
 
 
 
 
 
 
Are the me thods 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.  
 
Unable to assess  
 
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 indicate the quality of language in the manuscr ipt: 
 
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 reimbursemen ts, fees, funding, 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 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 org anization 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 o f 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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