Review for 10.1186/s12876-022-02132-0 (2022)

Reviewer’s report
Title: 
Are Gastrointestinal Symptoms Associated with Higher Risk of Mortality
in COVID-19 Patients? A Systematic Review and Meta-Analysis
Version: 
4 
Date: 
24 Jan 2022
Reviewer's report:
"PEER REVIEWER ASSESSMENTS: 
OBJECTIVE - Full research articles: is there a clear objective that addresses one
or several testable research questions? (Brief or other article types: is there a
clear objective?)
Yes - there is a clear objective
DESIGN - Is the current approach (including controls and analysis protocols)
appropriate for the objective?
Yes - the approach is appropriate
EXECUTION - Are the experiments and analyses performed with sufficient
technical rigor to allow confidence in the results?
Yes - experiments and analyses were performed appropriately
STATISTICS - Is the use of statistics in the manuscript appropriate?
Yes - appropriate statistical analyses have been used in the study
INTERPRETATION - Is the current interpretation/discussion of the results
reasonable and not overstated?
Yes - the author's interpretation is reasonable
OVERALL MANUSCRIPT POTENTIAL - Has the author addressed your
concerns sufficiently for you to now recommend the work as a technically sound
contribution? If not, can further revisions be made to make the work technically
sound?
Yes - current version is technically sound
PEER REVIEWER COMMENTS: 
GENERAL COMMENTS: Thanks for re-submitting this paper for review. I am
satisfied that the reviewers have carefully assessed my previous comments and
have satisfactorily addressed them.
ADDITIONAL REQUESTS/SUGGESTIONS: 
I am satisfied with the current version of the manuscript and recommend this be
accepted for publication."
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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
Is the use of statistics and treatment of uncertainties appropriate?
Yes
Is the presentation of the work clear?
Yes
Are the images in this manuscript (including electrophoretic gels and blots) free
from apparent manipulation?
Yes