Review for 10.1186/s12876-022-02191-3 (2022)

Reviewer’s report
Title: 
Characterization of short-chain fatty acids in patients with ulcerative
colitis: a meta-analysis
Version: 
0 
Date: 
02 Feb 2022
Reviewer's report:
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thank you for the opportunity to review this meta-analysis. in the introduction,
ulcerative colitis is not only limited to the colon but to the rectum and colon. 
in the chapter on materials and methods, the primary and secondary objectives
are not clearly stated. similarly, did the authors exclude articles according to the
language of publication? 
if the authors did a subgroup analysis according to disease severity, did the
authors correlate the biological results according to the luminal extension of the
disease? 
Is there a correlation between biological values and disease prognosis, in
particular, the use of surgery? 
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Is the study design appropriate to answer the research question (including the use
of appropriate controls), and are the conclusions supported by the evidence
presented?
Yes
Are the methods sufficiently described to allow the study to be repeated?
Yes
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Yes
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Yes
Are the images in this manuscript (including electrophoretic gels and blots) free
from apparent manipulation?
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