Review for 10.1186/s12876-016-0479-3 (2016)

Reviewer ’s report  
 
Title: Liver Elasticity Measurement Before and After Biliary Drainage in Patients With  
Obstructive Jaundice -A Prospective Cohort Study  
 
Version: 0 Date: 21 Jan 2016  
 
Reviewer: Eric Cha k 
 
Reviewer's report:  
 
1. This is an interesting proof of concept manuscript showing the decrease in liver elastography 
scores as measured by transient elastography and virtual touch quantification.  This is not 
entirely novel and other studies (for example: Milloniq et al Hepatology 2008) has showed 
something similar --that cholestasis may confound elastography measurements.  Despite 
being underpowered, the authors were still able to find a statistically significant  decrease in 
elastography scores after drainage.  
2. The authors have accurately concluded that the serum liver fibrosis scores are inaccurate 
measures of liver fibrosis in cholestasis as changes in AST and GGT drive decreases in these 
scores.  
3. In Figure 4, VTQ -L/VTQ -R and VTQ -L/TE showed strong correlation, but VTQ -R/TE was 
not as strong (r=0.63).  What is the reason for this difference between left and right liver 
measurements?  
4. Baseline elastography scores are high before and after draina ge.  While these values could be 
due to cholestasis, which lab tests were sent to completely rule out primary liver fibrosis?  
Were any liver biopsies performed to rule out primary liver fibrosis?  
5. Of the 20 patients recruited, only 10 patients had post -drainage measurements.  Could this be 
explained?  A control group comparison would be ideal, but not done in this study.  
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 commen ts to the authors.  
 
No 
 
 
 
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 rev iew?  
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 ma nuscript:  
 
Acceptable  
 
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