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  
 
Declar ation of competing interests  
Please complete a declaration of competing interests, considering the following questions:  
1. Have you in the past five years received reimbursements, fees, funding, or salary from an 
organisation that may in any way gain or lose financially from the publication of this 
manuscript, either now or in the future?  
2. Do you hold any stocks or shares in an organisation that may in any way gain or lose 
financially from the publication of this manuscript, eithe r now or in the future?  
3. Do you hold or are you currently applying for any patents relating to the content of the 
manuscript?  
4. Have you received reimbursements, fees, funding, or salary from an organization that 
holds or has applied for patents relatin g to the content of the manuscript?  
5. Do you have any other financial competing interests?  
6. Do you have any non -financial competing interests in relation to this paper?  
If you can answer no to all of the above, write 'I declare that I have no competing interests' 
below. If your reply is yes to any, please give details below.  
I declare that I have no competing interests.  
I agree to the open peer review policy of the journal. I understand that my name will be included 
on my report to the authors and, if the manuscript is accepted for publication, my named report 
including any attachments I upload will be posted on the websi te along with the authors' 
responses. I agree for my report to be made available under an Open Acce ss Creative Commons 
CC-BY license ( http://creativecommons.org/licenses/by/4.0/ ). I understand that any comments 
which I do not wish to be included in my name d report can be included as confidential comments 
to the editors, which will not be published.  
I agree to the open peer review policy of the journal  
 
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  
 
Declar ation of competing interests  
Please complete a declaration of competing interests, considering the following questions:  
1. Have you in the past five years received reimbursements, fees, funding, or salary from an 
organisation that may in any way gain or lose financially from the publication of this 
manuscript, either now or in the future?  
2. Do you hold any stocks or shares in an organisation that may in any way gain or lose 
financially from the publication of this manuscript, eithe r now or in the future?  
3. Do you hold or are you currently applying for any patents relating to the content of the 
manuscript?  
4. Have you received reimbursements, fees, funding, or salary from an organization that 
holds or has applied for patents relatin g to the content of the manuscript?  
5. Do you have any other financial competing interests?  
6. Do you have any non -financial competing interests in relation to this paper?  
If you can answer no to all of the above, write 'I declare that I have no competing interests' 
below. If your reply is yes to any, please give details below.  
I declare that I have no competing interests.  
I agree to the open peer review policy of the journal. I understand that my name will be included 
on my report to the authors and, if the manuscript is accepted for publication, my named report 
including any attachments I upload will be posted on the websi te along with the authors' 
responses. I agree for my report to be made available under an Open Acce ss Creative Commons 
CC-BY license ( http://creativecommons.org/licenses/by/4.0/ ). I understand that any comments 
which I do not wish to be included in my name d report can be included as confidential comments 
to the editors, which will not be published.  
I agree to the open peer review policy of the journal  
 
Please review this paper.
user
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  
 
Declar ation of competing interests  
Please complete a declaration of competing interests, considering the following questions:  
1. Have you in the past five years received reimbursements, fees, funding, or salary from an 
organisation that may in any way gain or lose financially from the publication of this 
manuscript, either now or in the future?  
2. Do you hold any stocks or shares in an organisation that may in any way gain or lose 
financially from the publication of this manuscript, eithe r now or in the future?  
3. Do you hold or are you currently applying for any patents relating to the content of the 
manuscript?  
4. Have you received reimbursements, fees, funding, or salary from an organization that 
holds or has applied for patents relatin g to the content of the manuscript?  
5. Do you have any other financial competing interests?  
6. Do you have any non -financial competing interests in relation to this paper?  
If you can answer no to all of the above, write 'I declare that I have no competing interests' 
below. If your reply is yes to any, please give details below.  
I declare that I have no competing interests.  
I agree to the open peer review policy of the journal. I understand that my name will be included 
on my report to the authors and, if the manuscript is accepted for publication, my named report 
including any attachments I upload will be posted on the websi te along with the authors' 
responses. I agree for my report to be made available under an Open Acce ss Creative Commons 
CC-BY license ( http://creativecommons.org/licenses/by/4.0/ ). I understand that any comments 
which I do not wish to be included in my name d report can be included as confidential comments 
to the editors, which will not be published.  
I agree to the open peer review policy of the journal  
 
assistant