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: 24 Jul 2019
Reviewer: Alejandra Cardelle-Cobas
Reviewer's report:
The article deals with the association of low activity of disaccharidases and general
gastrointestinal symptoms in children. From my point of view, the manuscript content is, ingeneral, well written and with adequates tables including the data obtained. The methodology isadapted to the objectives of the study and the underlying science is sound. In fact, I find that theseproblems associated to low disaccharidases activity should be more deeply studied since thenumber of cases is continuosly increasing. As the authors indicate in their work more largersamples size are necessary to evidence this relationship.The purposes of the work and the experimental findings are clearly described and the resultscontribute to the previous studies developed. I only have a suggestion for the authors, it should beinteresting to have include some conclusions about if differences were found, or not, depending onthe age (teenager, pre-teenager), on the race or on the sex. With a sample including 347 children itshould be a shame not to draw any more conclusionsIn any case, I consider the manuscript should be accepted for publication
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.
YesAre the conclusions drawn adequately supported by the data shown?
If not, please explain in your comments to the authors.
YesAre 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 furtherassessment 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:
AcceptableDeclaration of competing interests
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