Review for 10.1186/s12876-018-0760-8 (2018)

Reviewer ’s report  
 
Title:  Functional gastrointestinal diseases and psychological maladjustment, pers onality traits 
and quality of life  
 
Version: 0 Date: 10 Oct 2017 
 
Reviewer:  Lukas  Van Oudenhove  
 
Reviewer’s report:  
 
This is an interesting study on a relevant topic, namely personality traits and QoL in adolescent 
FGIDs.  
 
Although the topic is of interest and the study generally well -conducted and well -written, I  
would like to see the following issues addressed before this paper can be considered further for 
publication.  
 
 
GENERAL REMARK  
 
There is room for improvement of English spelling, grammar, and syntax.  
 
 
INTRODUCTION  
 
Although the introduction is generally clear and concise and the aims are clearly stated, 
references are too sparse, for example in the second paragraph. Furthermore, the authors seem to 
overstate the novelty of the study, for example in the last sentence of the second paragraph where 
they stat e that there is no research on personality in FGID - this is not the case, at least not in the 
adult literature. I would recommend performing a more thorough literature search and adapt the 
introduction accordingly. Finally, in the last paragraph on their third aim, the authors list known 
factors determining healthcare consultation in children with abdominal pain, but they don't seem 
to take these into account in the present study. How could this have affected the results? The 
same applies to the QoL analys is, other factors known to influence QoL in FGID such as co -
morbid anxiety, depression, and extraintestinal symptoms are not taken into account. This should 
at minimum be addressed as a severe limitation. Generally, the limitations section is too limited 
itself.  
 
 
METHODS  
 
A. Sample selection.  
 
Was there no single student who refused participation? A 100% response rate is quite hard to 
believe?!  
D. Statistical analysis  
 
Please clarify what is meant by "Z test"?  
 
 
RESULTS  
 
C. Psychological maladjustment  
 
Multiple bivariate comparisons by t -tests have been performed in this section. I think the authors 
should indicate which comparisons survive some kind of multiple testing correction. Bonferroni 
may be overly conservative, but the authors may consider using  stepdown Bonferroni or FDR 
correction for the total number of bivariate t -test being performed. The same applies to sections 
D and E of the results.  
 
I hope these suggestions will help in further improving the manuscript.  
 
Are the methods 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.  
 
No 
 
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 th e 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 be ing 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, 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 i nterests 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.  
 
no competing interests  
 
I agree to the  open peer review policy of the journal. I understand that my name will be included 
on my report to the authors and, if the manuscript is accepted for publication, my named report 
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to the editors, which will not be published . 
 
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