Review for 10.1186/s12876-018-0868-x (2018)

Reviewer’s report
Title: Vedolizumab use after failure of TNF- α antagonists in children and adolescents with
inflammatory bowel disease
Version: 1 Date: 19 Jul 2018
Reviewer: Oren Ledder
Reviewer's report:
This work is a praiseworthy attempt to help boost the data on Vedolizumab in pediatric IBD. However
the major concern is the small sample size when 3 sizable retrospective reports have already been
published. The contribution from this study is hence somewhat limited.
Specific comments:
All data must be presented as mean (+/- SD) or median (+/- IQR).
It is difficult to ascertain how much of the response was related to adjunct therapies (eg corticosteroids,
tacrolimus) as opposed to just VDZ. The data should be presented in a format whereby this is easily
understood from the text, or better yet, from the figures or tables.
Along the same line, corticosteroid-free or EEN-free remission would be a better representation of drug
effect rather then just clinical remission.
In  the  discussion  the  text  "In  the  largest  paediatric  cohort  study  on  vedolizumab  thus  far,  no
improvement in height velocity and no significant weight gain were observed during treatment" is
repeated in the adjacent paragraph.
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.
Yes
Are the conclusions drawn adequately supported by the data shown?
If not, please explain in your comments to the authors.
Unable to assess
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
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