Review for 10.1186/s12876-020-01261-8 (2020)

Reviewer’s report
Title: Gastroesophageal reflux disease in a typical African population A symptom-based multicenter
study.
Version: 1 Date: 15 Apr 2019
Reviewer: Shobna J. Bhatia
Reviewer's report:
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This is a well conducted study done to assess the frequency of GERD symptoms and their  frequency in
Nigeria. 
1. The GERDQ is designed to be used as a self-assessment questionnaire. In order to be used in
Nigeria, the translation in local language would be needed. The authors mention that "administration of
the study questionnaire" was done. It is not clear whether it was the paramedical workers or doctors
who administered it. 
2. There are no details about how FGID was diagnosed. Mention of Rome III criteria is mentioned, but
no details are available. Putative risk factors of GERD were assessed, however there is no mention of
the risk factors which were assessed or whether it was a yes/no response / frequency.
3. The Results are sketchy. Some baseline parameters of GERD patients are mentioned ; There are no
details  for  the  rest  of  the  population.  These  data  would  be  helpful  to  understand  whether  any
differences exist between the people with GERD and those without.
4. The number of patients with various symptoms are listed in Table, but the actual frequency of
symptoms in patients (weekly / monthly etc) is not available. 
5. The number of overall subjects with FGID in the entire population  is not mentioned. The figure
shows overlap in percentages; actual numbers would be helpful. 
6. It is not clear why farmers had higher reflux. Authors should explain this.
Are the methods appropriate and well described?
If not, please specify what is required in your comments to the authors.
No
Does the work include the necessary controls?
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Unable to assess
Are the conclusions drawn adequately supported by the data shown?
If not, please explain in your comments to the authors.
Yes
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 recommend additional statistical review
Quality of written English
Please indicate the quality of language in the manuscript:
Acceptable
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