Review for 10.1186/s12876-021-01605-y (2021)

Reviewer’s report
Title: 
Patient experience with NER1006 as a bowel preparation for colonoscopy:
a prospective, multicenter US survey
Version: 
1 
Date: 
17 Sep 2020
Reviewer's report:
PEER REVIEWER ASSESSMENTS: 
OBJECTIVE - Full research articles: is there a clear objective that addresses a
testable research question(s) (brief or other article types: is there a clear
objective)?
Yes - there is a clear objective
DESIGN - Is the current approach (including controls and analysis protocols)
appropriate for the objective?
No - there are minor issues
EXECUTION - Are the experiments and analyses performed with technical rigor
to allow confidence in the results?
Yes - experiments and analyses were performed appropriately
STATISTICS - Is the use of statistics in the manuscript appropriate?
Yes - appropriate statistical analyses have been used in the study
INTERPRETATION - Is the current interpretation/discussion of the results
reasonable and not overstated?
No - there are minor issues
OVERALL MANUSCRIPT POTENTIAL - Is the current version of this work
technically sound? If not, can revisions be made to make the work technically
sound?
Probably - with minor revisions
PEER REVIEWER COMMENTS: 
GENERAL COMMENTS: 
Overall Impression 
This is a potentially very important paper because one of the major problems
with colonoscopy is the compliance with the 
bowel prep by the patients. 
This
study shows that this specific prep was well tolerated by the vast majority of
patients and esp. those who had had a previous bowel prep. One major limitation
of this study is that the adequacy of this bowel prep was not (apparently)
evaluated and this is crucial, because if the bowel prep (which is considerably
different from the usual PEG preps of requiring ingestion 2 and 4 liters of
volume) has a substantial percentage of inadequate preps, and these patients
require a repeat colonoscopy, then the conclusion of the study may be quite
different. 
What have the authors done well 
1. Congratulations getting 1598 of the 1606 patients to complete the survey -
very impressive!—98%!!!
2. The wide geographic region is important, but ideally you would give more
info concerning racial and economic status of patients 
2. The taste, volume, different regimens, and overall satisfaction of the prep is
very important to compliance - well done.
In what ways does it not meet best practice 
1. While the authors have answered the question about ease of jntake by the
patients, there are no data on the adequacy of the prep by the gastroenterologist.
This is very important data; the questionnaire could also have asked the patients
if their doctor told them that the prep was not satisfactory or that they needed to
redo the colonoscopy because the prep was not satisfactory. This is a major
limitation. I am sorry to have to ask, but if there is another paper where the
colonoscopists were surveyed about the adequacy of the prep visually, then those
data and this MUST be combined!
REQUESTED REVISIONS: 
Are there additional revisions the authors should make/consider 
1. Line 46 - you should also include the percentages of patients who felt that this
prep was worse than the others they have taken.
2. Line 77 - I would reword "bowel preparation volume " to "the volume of the
bowel preparation required" - it reads better.
3. Line 70 - should you add the phrase "in comparison to the more typical 2-4 L
original PEG prep"?
4. Lines 98-111 - should you also specify that lack of intake other than this prep
during the bowel prep and maybe address the diet on day 1 of the 2-day prep
regimen? Also, what was the volume of each "dose of the PEG solution or was it
a powder"? Was the dose a substance that needed to be dissolved in water?
Some readers will not know of the details of this prep.
5. Lines 113-114 - best to define what the actual monetary compensation was in
US dollars.
6. Lines 116-122 - was this a visual analog scale (VAS)?; if so, best to state it.
7. Line 118 - when you say "volume requirement", I am assuming you are
referring 
to the volume of liquid that the company "requires" the patients to
ingest. 
8. Lines 29 and 95 - please define in the text as well as the table (not everyone
will go to the table and this is an important point) 
the geographic area from
which the patients participated; this is important because, on line 165 you say
"across a wide US geographic area"; also, maybe a statement about racial and
economic diversity; if you do not have these data, then this needs to be a
limitation. 
9. Lines 171-181 - please also comment on the adequacy of the preparation by
the colonoscopies, because if the prep was satisfactory in only 85% and those
patients needed another colonoscopy, then your conclusion would be much
different. 
Line 200 - best to further emphasize that no attempt was made to determine
whether the prep was considered satisfactory to the gastroenterologist or surgeon
performing the procedure and no information (if you have it, give it!) about need
for a repeat colonoscopy is available. This is a major limitation of this study, and
the data sheet should have inquired about the adequateness of the prep to the
colonoscopies - too bad that was not part of the survey.
10. Competing interests: better define if MBCM is a physician and you must
define clearly whether Salix Pharmaceutical had veto power to publish this work
- anytime an industry individual is an author this needs to be defined clearly and
in-depth.
11. Funding: this is blocked out for this reviewer. The funding needs again to be
perfectly clear as to what Salix paid for, whether any of the non-Salix authors
received direct monetary compensation for their participation. 
12. In the methods section - who or how was the data collected, who analyzed it
(this needs to be perfectly clear!) If by the company Salix, then who confirmed
the data entry and the data analysis? This is not evident either in the methods or
authors' contributions.
13. Table 2 at bottom - what is line 328 referring to?
Because this reviewer is blinded to the authors, I assume by the initials that this
was a published abstract. Was this presented at a meeting? If so, please define
the meeting, when and where, and if it was a poster or podium presentation.
14. Were all the colonoscopies performed by gastroenterologists? 
or were there
also surgeons and even 
possibly PAs doing these? 
Best to define this and maybe
use the term "colonoscopists" rather than "gastroenterologists".
Publons Reviewer Recognition
. Springer Nature can send verification of this
review directly to Publons (a subsidiary of Clarivate Analytics). If you would
like to take advantage of this service, please click on the “Yes” option below.
Your name, email address, title of the reviewed manuscript, name of the journal,
and date of your review submission (the “Review Data”) will then be transmitted
to Publons upon publication of the manuscript. If you have already registered at
Publons, they will notify you of the receipt of this review and update your profile
as per your settings and their policy. If you are not registered with Publons, you
will receive an email from them asking you to register in order for them to be
able to recognize your review on your new profile page. Publons may use the
Review Data to generate derivative metadata for the benefit of Publons and you
as a reviewer, carefully considering the sensitivity of such information. For
example, Publons may verify your record as a reviewer by updating your profile
published on its webservice if you have registered for such service or help
editors to identify candidate reviewers. Please find the details of processing in
Publons’ privacy policy 
https://publons.com/about/terms
No
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 financially 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.
This reviewer has been recruited by a partner organization, Research Square.
Reviewers with declared or apparent competing interests are not utilized for
these reviews. This reviewer has agreed to publication of their comments online
under a Creative Commons Attribution License attributed to Research Square
and was paid a small honorarium for completing the review within a specified
timeframe. Honoraria for reviews such as this are paid regardless of the reviewer
recommendation.
Reviewer Publication Consent.
 I agree for my report to be made available
under an Open Access Creative Commons CC-BY License (
http://creativecommons.org/licenses/by/4.0
) if this manuscript is accepted for
publication. Any comments that I do not wish to be included in the published
report have been included as confidential comments to the editor, which will not
be published.
If you are not happy for us to publish this report, please contact the editorial
office before completing the review.
If you wish, you can include your name in your published report. Please note
you must decide whether to include your name at the start of the process and
confirm this decision whenever prompted. If you change your decision later, we
will not be able to publish your name.
I agree to the terms of the CC-BY 4.0 license; please publish my name with my
report.
Is the study design appropriate to answer the research question (including the use
of appropriate controls), and are the conclusions supported by the evidence
presented?
No
Are the methods sufficiently described to allow the study to be repeated?
Yes
Is the use of statistics and treatment of uncertainties appropriate?
Yes
Is the presentation of the work clear?
Yes
Are the images in this manuscript (including electrophoretic gels and blots) free
from apparent manipulation?
Yes