Review for 10.1186/s12876-018-0755-5 (2018)

Reviewer ’s report  
 
Title:  Unexplained chronic liver disease in Ethiopia: a cross -sectional study  
 
Version: 0 Date: 19 Dec 2017 
 
Reviewer:  Bhavana  Bhagya Rao  
 
Reviewer’s report:  
 
This is an interesting study from a resource deplete institution, that tries to determine the 
prevalence of various etiologies for chornic liver disease (CLD) in their population. However it 
has shortcomings as follows:  
 
It is unclear why the authors have excluded patients with prior diagnosis of chronic liver disease 
and only included the incid ent cases.  
 
Were all the described serological, microbiologic, biochemical tests performed on all of the 
study subjects?  
 
What percentage of study subjects received liver biopsy? How was it determined as to who 
would receive liver biopsy? Did any of the pati ents who had an identified possibly etiology, 
undergo liver biopsy to confirm that etiology?  
 
In Table 2, testing the statistical difference in demographic characteristics between the etiology 
known and unknown group does not carry much clinical relevance. The authors could remove 
the significance column from the table.  
 
A comparison of the clinical symptoms, laboratory features between the etiology known and 
unknown groups also does not carry much clinical relevance.  
 
Tables maybe listed at the bottom of the manuscript, after the references, rather than within the 
text. 
 
The results of the study are limited by the substantial number of patients with unknown etiology 
who did not get subsequent liver biopsy.  
 
The diagnostic criteria for NASH used by the authors is quite non specific and may have led to 
significant errors in estimation of prevalence.  
 
While authors say that the prevalence of unexplained CLD is higher in Ethiopia, once could 
argue that that is sig nificantly impacted by the lack of the gold standard liver biopsy and 
histopathologic analysis in these cases.  
 
While the authors comment that the use of khat was very frequent among the CLd patients, this 
study does not include a control group where khat u se can be compared. Hence no conclusions 
regarding any possible association of khat use with CLD can be made with this study.  
 
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?  
If not, please specify which controls are required in your comments to the authors.  
 
No 
 
Are the conclusions drawn adequately supported by the data shown?  
If not, please explain in your comments to the authors.  
 
No 
 
Are you able to assess any statistics in the manuscript or would you recommend a n 
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 statistics  
 
Quality of written English  
Please indicate the  quality of language in the manuscript:  
 
Acceptable  
 
Declaration of competing interests  
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3. Do you hold or are you currently applying for any patents relating to the content of the 
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5. Do you have any other financial competing interests?  
 
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below. If your reply is yes to any, please give details below.  
 
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