Review for 10.1186/s12876-018-0856-1 (2018)

Reviewer ’s report  
 
Title:  Breath test using 13C methacetin does not seem to be useful in the assessment of liver 
function in girls with anorexia nervosa: a case control study  
 
Version: 1 Date: 27 May 2018 
 
Reviewer:  Grzegorz  Oracz  
 
Reviewer’s report:  
 
Overview: The authors evaluate the usefulness of the 13C labeled Methacetin Breath Test 
(MBT) in the diagnostics of the liver function in girls with eating disorders. The study is original, 
prospective, performed in large group of girls with AN. Results of the study show that 13C 
methacetin metabolism in female patients with AN is significantly increased in comparison to 
healthy controls. Authors concluded that this test is not useful in in the assessment of liver 
function in girls with AN. In my opinion despite of negative results it is interesting study.  
 
 
Minor criticisms:  
 
1. page 2 line 15 and page 4 line 13 - DSM -5 - lack of explanation of the abbreviation  
 
2. Authors affiliations No 1 and No 2 - it seems that it is the same affiliation  
 
3. page 2 line 1 in abstract - lack of mean age of the patients  
 
4. In my opinion it is worth to underline that BMI percentile is more useful in children than BMI  
 
5. page 5 - after the Wagner company name should be country - Germany  
 
6. Table 3 - page 10  
 
BILIRUBIN - I'm sure authors by mistake putted mg/dl!!!  It should be umol/l?  
 
in table is lack of reference values of the studied parameters  
 
mean AST and ALT values are within no rmal values. In my opinion authors should give results 
of AST and ALT in these 5 girls with elevated results.  
 
7. The time of the study (years) is not given  
 
Are t he 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 assess any statistics in the manuscript or would you recommend an 
additional stat istical 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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