Review for 10.1186/s12876-020-01443-4 (2020)

Reviewer’ s report
Title: A Retrospective Study on the Association of Gastrointestinal Symptoms in Children with
Low Lactase Activity and Low Activity of Other Disaccharidases
Version: 0Date: 17 Dec 2019
Reviewer: Research Square Reviewer 1
Reviewer's report:
PEER REVIEWER ASSESSMENTS:OBJECTIVE - Full research articles: is there a clear objective that addresses a testable research
question(s) (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?No - there are minor issues
EXECUTION - Are the experiments and analyses performed with technical rigor to allow
confidence in the results?No - there are minor issues
STATISTICS - Is the use of statistics in the manuscript appropriate?
No - there are issues with the statistics in the study
INTERPRETATION - Is the current interpretation/discussion of the results reasonable and not
overstated?No - there are minor issues
OVERALL MANUSCRIPT POTENTIAL - Is the current version of this work technically sound?
If not, can revisions be made to make the work technically sound?Maybe - with major revisions
PEER REVIEWER COMMENTS:GENERAL COMMENTS:
It is a large study, though retrospective. The findings are not earth-shattering but the methodologyis reasonably good.
REQUESTED REVISIONS:
1. Abdominal pain is a subjective symptom. How was it defined for the purpose of your study?
2. I suggest to omit the phrase "There may be an association 16 between low combined sucrase,
maltase, and palatinase and weight loss (OR=32.2340; 95% 17 CI=1.50-692.55; p<0.05; N=2)"from the abstract as this was based on 2 cases only.3. The authors argue that the study by Chumpitazi et al. [ref 10] was under-powered. Pleaseprovide power calculation of your study, post-hoc.4. How the exclusion of villous atrophy strengthened the study?5. Do the authors think that some participants might have had genetic predisposition to lowlactase, sucrase, maltase, and palatinase activity?6. English needs to be reviewed for style and grammar.
Are the methods appropriate and well described?
If not, please specify what is required in your comments to the authors.
NoDoes the work include the necessary controls?
If not, please specify which controls are required in your comments to the authors.
NoAre the conclusions drawn adequately supported by the data shown?
If not, please explain in your comments to the authors.
NoAre 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 statisticsQuality of written English
Please indicate the quality of language in the manuscript:
Needs some language corrections before being publishedDeclaration 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 thismanuscript, either now or in the future?
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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?
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If your reply is yes to any, please give details below.
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declared or apparent competing interests are not utilized for these reviews. This reviewer hasagreed to publication of their comments online under a Creative Commons Attribution Licenseattributed to Research Square and was paid a small honorarium for completing the review within aspecified timeframe. Honoraria for reviews such as this are paid regardless of the reviewerrecommendation.
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