Review for 10.1186/s12876-016-0543-z (2016)

Reviewer ’s report  
 
Title: Role of vitamin D3 combined to alginates in preventing acid and oxidative injury in  
cultured gastric epi thelial cells  
 
Version: 2 Date: 24 Jun 2016  
 
Reviewer: Thomas Wex  
 
Reviewer's report:  
 
The authors addressed most aspects in their revision appropriately, but included quite a lot of 
new data that makes it difficult to access the essentials of the manuscript. The aspect of primary 
cells needs to  be included in the main part and not just as supplementary information. This 
relates also to the abstract of the manuscript  
 
 
Furthermore, there is still a question concerning the statistical analysis. The authors perform 
presumably >100 sub analyses. The methodology is not really clear on this issue.  The Man -
Whitney U test is used for analyzing relative changes of responses. But primary data seem to be 
normally distributed, since they are all presented as mean and standard deviations throughout the 
manusc ript. The Man -Whitney U test is not appropriate for normally distributed data. Authors 
need to revise and/or discuss  this issue in response and in the manuscript. Furthermore, authors 
need to present the P -values for the ANOVA test and identify the tests used in the figure legends.  
 
 
The authors need still carefully review the manuscript for typos and formal mistakes. Symbols 
such as "µ" are missing and there are several dash line interrupting words (e.g. con -sti-pa-tion on 
page 5 and several others).  
 
 
Figure 5: Please use letters a -k from lower panel to identify corresponding rows in upper panel.  
 
 
Figures of supplementary data: Data should be identical presented (patterns, colour) than those of 
GTL -16 cells.  
 
 
 
 
 
 
 
 
   
 
Are the methods appropriate and well described?  
If not, please specify what is required in your comments to the authors.  
 
Yes 
 
Does the work i nclude 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 indicate the quality of language in the manuscript:  
 
Needs some language corrections before bei ng published  
 
Declaration of competing interests  
Please complete a declaration of competing inter ests, 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 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 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 you r reply is yes to any, please give details below.  
 
'I declare that I have no competing interests'  
  
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