Review for 10.1186/s12876-018-0896-6 (2018)

Reviewer ’s report  
 
Title: Evaluating gut microbiota profiles from archived fecal samples  
 
Version: 1 Date: 18 Sep 2018  
 
Reviewer: Robert Kraaij  
 
Reviewer's report:  
 
The issues raised after the first review were addressed properly. Especially, reaching the 
conclusion that the different sample types do differ in their composition but can be used for 
analyses by limiting to samples from the same type, confirmed what I expected and is a message 
the microbiom e community would want to know.  
Two minor points:  
line 258: smaller than sign (<) should be used instead of greater than (>)  
Fig. 4B: the Bray -Curtis distance of sample pairs (replicates) is normally around 0.2. This one is 
quite high, can that be explained?  
 
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.  
 
Yes 
 
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 as sess any statistics in the manus cript or would you recommend an 
additional statistical review?  
If an additional statistical review is recommended, please speci fy 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  
 
 
 
Declaration of competing interests  
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below. If your reply is yes to any, please give details below.  
 
I dec lare that I have no competing interests  
 
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