Reviewer ’s report  
 
Title: The H.O.U.S.E. Classification: A novel endoscopic retrograde cholangiopancreatography 
(ERCP) complexity grading scale.  
 
Version: 0 Date: 08 Jun 2016 
 
Reviewer:  Amy  Tyberg  
 
Reviewer’s report:  
 
This is a great hypothesis: to create a scoring system that can stratify ERCPs by complexity to 
help triage p atients to the appropriate clinical environment, help predict expected complication 
rates post -procedure, assist in choosing appropriate learning cases for trainees, and standardize 
billing and reporting across centers. Strengths of the study includes the large number of patients 
included, as well as evidence of validity of the scoring system by demonstrating a correlation 
between increasing complication rates (specifically PEP) with increasing complexity on the 
scoring system However, there are some issues  that should be addressed:  
 
1. The scoring system needs to be explained in the methods section (not just in a table) since it is 
the main feature of the article.  
 
2. Please mention in the results section how many patients were in each group.  
 
3. As mention ed in the article, many of the criteria in the scoring system are factors that cannot 
be anticipated in advance of the procedure. This is problematic when claiming that the scoring 
system can be used to determine the type of hospital the procedure should b e performed at since 
the true score would not be known until the procedure is ongoing. Perhaps it would be useful as a 
secondary analysis to separate out those factors that can be predicted pre -procedure and see if the 
score remains valid using just the pr edictable criteria. If so, it could truly be a useful tool for 
triaging patients to the appropriate clinical setting prior to embarking on a procedure.  
 
4. It appears that House 1 and 2 groups had more patients with acute pancreatitis prior to the 
procedur e - was this difference significant? If so, could the lower PEP rate in House 1 be because 
a higher percentage of patients already had pancreatitis and thus were not included as having 
PEP? Or were those patients evaluated for worsening of pancreatitis pos t-procedure and included 
in the PEP count?  
 
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.  
 
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 sta tistics in the manuscript or would you recommend an 
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:  
 
Needs some language corrections before being published  
 
Declaration 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 
financial ly from the publication of this manuscript, either 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 relating 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 competi ng 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 website along with the authors' 
responses. I agree for my report to be made available unde r an Open Access 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 named 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: The H.O.U.S.E. Classification: A novel endoscopic retrograde cholangiopancreatography 
(ERCP) complexity grading scale.  
 
Version: 0 Date: 08 Jun 2016 
 
Reviewer:  Amy  Tyberg  
 
Reviewer’s report:  
 
This is a great hypothesis: to create a scoring system that can stratify ERCPs by complexity to 
help triage p atients to the appropriate clinical environment, help predict expected complication 
rates post -procedure, assist in choosing appropriate learning cases for trainees, and standardize 
billing and reporting across centers. Strengths of the study includes the large number of patients 
included, as well as evidence of validity of the scoring system by demonstrating a correlation 
between increasing complication rates (specifically PEP) with increasing complexity on the 
scoring system However, there are some issues  that should be addressed:  
 
1. The scoring system needs to be explained in the methods section (not just in a table) since it is 
the main feature of the article.  
 
2. Please mention in the results section how many patients were in each group.  
 
3. As mention ed in the article, many of the criteria in the scoring system are factors that cannot 
be anticipated in advance of the procedure. This is problematic when claiming that the scoring 
system can be used to determine the type of hospital the procedure should b e performed at since 
the true score would not be known until the procedure is ongoing. Perhaps it would be useful as a 
secondary analysis to separate out those factors that can be predicted pre -procedure and see if the 
score remains valid using just the pr edictable criteria. If so, it could truly be a useful tool for 
triaging patients to the appropriate clinical setting prior to embarking on a procedure.  
 
4. It appears that House 1 and 2 groups had more patients with acute pancreatitis prior to the 
procedur e - was this difference significant? If so, could the lower PEP rate in House 1 be because 
a higher percentage of patients already had pancreatitis and thus were not included as having 
PEP? Or were those patients evaluated for worsening of pancreatitis pos t-procedure and included 
in the PEP count?  
 
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.  
 
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 sta tistics in the manuscript or would you recommend an 
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:  
 
Needs some language corrections before being published  
 
Declaration 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 
financial ly from the publication of this manuscript, either 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 relating 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 competi ng 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 website along with the authors' 
responses. I agree for my report to be made available unde r an Open Access 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 named 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: The H.O.U.S.E. Classification: A novel endoscopic retrograde cholangiopancreatography 
(ERCP) complexity grading scale.  
 
Version: 0 Date: 08 Jun 2016 
 
Reviewer:  Amy  Tyberg  
 
Reviewer’s report:  
 
This is a great hypothesis: to create a scoring system that can stratify ERCPs by complexity to 
help triage p atients to the appropriate clinical environment, help predict expected complication 
rates post -procedure, assist in choosing appropriate learning cases for trainees, and standardize 
billing and reporting across centers. Strengths of the study includes the large number of patients 
included, as well as evidence of validity of the scoring system by demonstrating a correlation 
between increasing complication rates (specifically PEP) with increasing complexity on the 
scoring system However, there are some issues  that should be addressed:  
 
1. The scoring system needs to be explained in the methods section (not just in a table) since it is 
the main feature of the article.  
 
2. Please mention in the results section how many patients were in each group.  
 
3. As mention ed in the article, many of the criteria in the scoring system are factors that cannot 
be anticipated in advance of the procedure. This is problematic when claiming that the scoring 
system can be used to determine the type of hospital the procedure should b e performed at since 
the true score would not be known until the procedure is ongoing. Perhaps it would be useful as a 
secondary analysis to separate out those factors that can be predicted pre -procedure and see if the 
score remains valid using just the pr edictable criteria. If so, it could truly be a useful tool for 
triaging patients to the appropriate clinical setting prior to embarking on a procedure.  
 
4. It appears that House 1 and 2 groups had more patients with acute pancreatitis prior to the 
procedur e - was this difference significant? If so, could the lower PEP rate in House 1 be because 
a higher percentage of patients already had pancreatitis and thus were not included as having 
PEP? Or were those patients evaluated for worsening of pancreatitis pos t-procedure and included 
in the PEP count?  
 
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.  
 
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 sta tistics in the manuscript or would you recommend an 
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:  
 
Needs some language corrections before being published  
 
Declaration 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 
financial ly from the publication of this manuscript, either 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 relating 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 competi ng 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 website along with the authors' 
responses. I agree for my report to be made available unde r an Open Access 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 named 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