Reviewer's report
Title:Clostridium leptum group bacteria abundance and diversity in the fecal
microbiota of patients with inflammatory bowel disease: a case-control study in
India
Version: 1Date:18 November 2012
Reviewer: Ashwin Ananthakrishnan
Reviewer's report:
Major comments:
1. The sample size of the cohorts is relatively small compared to many other
currently emerging studies on intestinal dysbiosis in IBD.
2. The focus is exclusive on C.leptum, in particular F. prausnitzii. The association
between reduced counts or diversity of this bacterial species and IBD has been
described in several previous cohorts. It would have been interesting to describe
a broader pattern of microbial dysbiosis in the IBD population from India.
Minor comments:
1. Perhaps the authors can provide a few more sentences on the ‘healthy
controls’ selected for their study. Was this from a gastroenterology practice as
well, or from a primary care general medical population?
2. In their statistical analysis, the authors refer to performing post-hoc Bonferroni
tests. This needs to be described in a little greater detail. What was the
Bonferroni adjusted p-value that represented statistical significance?
3. What medical treatments for their IBD were the patients on? Did any of the CD
patients have a history of surgical treatment of their disease? Had any patients
recently undergone a colonoscopy or colonoscopy preparation?
4. Throughout the manuscript – the authors present an overall p-value, followed
in parenthesis by p-values for the various between group comparisons. Perhaps
an easier way to present is just to describe the p-values between HC and CD,
and HC and UC. I don’t see the need for an overall between all 3-group p-values
when one is describing the subgroups anyway.
5. Was there a difference in colon counts or diversity by duration of IBD?
6. I think the authors conclusion that the changes in gut microbiome could be due
to dietary restrictions placed on IBD patients (Page 14) is somewhat speculative
and not backed up by data. In the absence of dietary information gathered as
part of their study, I would suggest excluding this speculation unless there is data
from other groups that provide objective evidence for this hypothesis.
Level of interest: An article of importance in its field
Quality of written English: Acceptable
Statistical review: No, the manuscript does not need to be seen by a
statistician.
Declaration of competing interests:
I declare that I have no competing interests.
Reviewer's report
Title:Clostridium leptum group bacteria abundance and diversity in the fecal
microbiota of patients with inflammatory bowel disease: a case-control study in
India
Version: 1Date:18 November 2012
Reviewer: Ashwin Ananthakrishnan
Reviewer's report:
Major comments:
1. The sample size of the cohorts is relatively small compared to many other
currently emerging studies on intestinal dysbiosis in IBD.
2. The focus is exclusive on C.leptum, in particular F. prausnitzii. The association
between reduced counts or diversity of this bacterial species and IBD has been
described in several previous cohorts. It would have been interesting to describe
a broader pattern of microbial dysbiosis in the IBD population from India.
Minor comments:
1. Perhaps the authors can provide a few more sentences on the ‘healthy
controls’ selected for their study. Was this from a gastroenterology practice as
well, or from a primary care general medical population?
2. In their statistical analysis, the authors refer to performing post-hoc Bonferroni
tests. This needs to be described in a little greater detail. What was the
Bonferroni adjusted p-value that represented statistical significance?
3. What medical treatments for their IBD were the patients on? Did any of the CD
patients have a history of surgical treatment of their disease? Had any patients
recently undergone a colonoscopy or colonoscopy preparation?
4. Throughout the manuscript – the authors present an overall p-value, followed
in parenthesis by p-values for the various between group comparisons. Perhaps
an easier way to present is just to describe the p-values between HC and CD,
and HC and UC. I don’t see the need for an overall between all 3-group p-values
when one is describing the subgroups anyway.
5. Was there a difference in colon counts or diversity by duration of IBD?
6. I think the authors conclusion that the changes in gut microbiome could be due
to dietary restrictions placed on IBD patients (Page 14) is somewhat speculative
and not backed up by data. In the absence of dietary information gathered as
part of their study, I would suggest excluding this speculation unless there is data
from other groups that provide objective evidence for this hypothesis.
Level of interest: An article of importance in its field
Quality of written English: Acceptable
Statistical review: No, the manuscript does not need to be seen by a
statistician.
Declaration of competing interests:
I declare that I have no competing interests.
Please review this paper.
user
Reviewer's report
Title:Clostridium leptum group bacteria abundance and diversity in the fecal
microbiota of patients with inflammatory bowel disease: a case-control study in
India
Version: 1Date:18 November 2012
Reviewer: Ashwin Ananthakrishnan
Reviewer's report:
Major comments:
1. The sample size of the cohorts is relatively small compared to many other
currently emerging studies on intestinal dysbiosis in IBD.
2. The focus is exclusive on C.leptum, in particular F. prausnitzii. The association
between reduced counts or diversity of this bacterial species and IBD has been
described in several previous cohorts. It would have been interesting to describe
a broader pattern of microbial dysbiosis in the IBD population from India.
Minor comments:
1. Perhaps the authors can provide a few more sentences on the ‘healthy
controls’ selected for their study. Was this from a gastroenterology practice as
well, or from a primary care general medical population?
2. In their statistical analysis, the authors refer to performing post-hoc Bonferroni
tests. This needs to be described in a little greater detail. What was the
Bonferroni adjusted p-value that represented statistical significance?
3. What medical treatments for their IBD were the patients on? Did any of the CD
patients have a history of surgical treatment of their disease? Had any patients
recently undergone a colonoscopy or colonoscopy preparation?
4. Throughout the manuscript – the authors present an overall p-value, followed
in parenthesis by p-values for the various between group comparisons. Perhaps
an easier way to present is just to describe the p-values between HC and CD,
and HC and UC. I don’t see the need for an overall between all 3-group p-values
when one is describing the subgroups anyway.
5. Was there a difference in colon counts or diversity by duration of IBD?
6. I think the authors conclusion that the changes in gut microbiome could be due
to dietary restrictions placed on IBD patients (Page 14) is somewhat speculative
and not backed up by data. In the absence of dietary information gathered as
part of their study, I would suggest excluding this speculation unless there is data
from other groups that provide objective evidence for this hypothesis.
Level of interest: An article of importance in its field
Quality of written English: Acceptable
Statistical review: No, the manuscript does not need to be seen by a
statistician.
Declaration of competing interests:
I declare that I have no competing interests.
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