Reviewer’s report
Title: 
Risk factors of poor prognosis and impairment of activities of daily living
in patients with hemorrhagic gastroduodenal ulcers
Version: 
0 
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)?
No - there are minor issues
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?
Yes - the author's interpretation is reasonable
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: 
* What is your overall impression of the study?
Interesting with some novel results relevant to care of older people and service
planning.
* What have the authors done well?
Provided an analysis of risk factors for impairment of daily living after
haemorrhagic ulcer, using retrospective methods. Analyses are appropriate. 
* In what ways does it not meet best practice?
The report of the study needs some additional detail and re-organisation of some
of the text to improve readability.
REQUESTED REVISIONS: 
Objective 
- minor issues. 
These are issues of clarity in reporting rather than
conduct of the research, please see my notes about the Abstract and methods, in
particularly the statements concerning specification of the risk factors and the
outcomes of interest 
in the report.
Design 
- minor issues. 
Only in that the study is of retrospective design and in a
single centre, which is discussed in the Discussion section as a potential
limitation.
Execution - appropriate, but some additional detail needs to be given in the
report for clarity.
Statistics - appropriate.
Interpretation - reasonable
Further details are provided below on a section by section basis.
Abstract 
Impairment of activities of daily living (ADL) due to haemorrhagic
gastroduodenal ulcers (HGU) has rarely been evaluated. The Background then
goes on cite several studies in which mortality and hospitalization have ben
studied. It might be better just to state that the authors evaluated Impairment of
activities of daily living (ADL) due to haemorrhagic gastroduodenal ulcer in the
abstract and expand on the lack of data other than mortality, hospitalizations and
healthcare costs in the Background, 
i.e. please make the 
case for the novelty of
this work in the Background section.
State risk factors and outcomes to be evaluated more clearly. 
The retrospective design of this study should be stated in the abstract.
Background.
Please see notes below regarding the choice of risk factors and outcomes. 
The
Background does not state why this research is novel and important for clinical
care and service planning. 
A minor edit to state this clearly would improve the
relevance of the paper.
e.g. 'Although previous studies have evaluated the risk factors for mortality of
HGU, and impairment of ADL has been evaluated in other disease, to date there
have been no studies that have evaluate which risk factors of HGU are
associated with impairment of ADL. 
This is important in both clinical care of
patients who are identified to be at risk of ADL impairment after HGU and for
planning of clinical and social care services. 
This is especially relevant in care of
the elderly since previous reports have revealed that advanced age is a risk factor
of poor outcomes for HGU patients (refs) '
Methods
How was the review conducted - by case notes, how were data extracted, was a
pro forma used and how was this developed (why were the data items chosen)?
Who performed the data extraction? 
How were data stored, collated, verified?
Please provide these details.
Inclusion 
and exclusion criteria. 
Please state these, e.g. co morbidities, residence
in care facilities.
How was ADL assessed? How were these data obtained once the patient had left
hospital care? The paper states that 
"Impairment of ADL was defined as
admission to care facilities after hospital discharge or the requirement of home
modification for rehabilitation at home." However, there is wide variation in
having minor adaptations in the home (which may have been needed for reasons
unrelated to HGU e.g. arthritis, and a full care package delivered in residential
care. This introduces uncertainty in the interpretation authors' of the results for
ADL and at the very least, there should be some discussion of this in the
Discussion section.
State risk factors 
- on reading this section data items are specified but it is not
clear how these were chosen as 'risk factors' (Were these chosen a priori ? ). The
reasons for these choices of risk factor and outcome should be stated in the
methods. 
It seems reasonable to select these risk factors and outcomes of
importance based on what is known from clinical practice, but some background
(with references) and reasons should be provided in the paper. The information is
present in the Background to some extent but there is no logical train of
reasoning between the existing knowledge and risk factors and outcomes chosen.
Some editing of the paper would solve this.
I am glad to see ethical approval stated clearly.
Statistical analysis
Statistics used appear to be appropriate, although a detailed opinion should be
sought from a medical statistician.
OR appears to be appropriate, given that the total number of exposed people is
not available, OR here is used as a measure of the strength of association
between exposure and outcome. Odds however are difficult for non specialists to
use and it would be helpful if there was an interpretation of the results in terms
of 
e.g. 'elderly patients who had pre-existing renal disease were x % more likely
to die within 30 days …'
Results
This section is clear enough, but the presentation of results could be better - at
present the format is rather dense and numerical. 
I accept that that is the nature
of the results, but the message is not easy to determine. A summary paragraph
providing the main results would be helpful, stating the clinical factors from
Table 1 and the results for the main outcomes of interest from Table 2. This
information appears throughout the Discussion and moving does this information
to the Results section would improve the readability.
Tables - all fine - possibly the OR could be plotted rather than being presented as
a table?
It is unclear why patients who resided in care facilities were included in the
initial data analyses, but later excluded. 
Since they were already experiencing
disruption to ADL presumably, these patients should have been excluded and the
inclusion/exclusion criteria should have been stated in the methods section (e.g..
malignancies, pre-existing dementia).
Discussion
The Discussion is good, as each finding is compared and contrasted with what is
already known. 
However please see my note above about summarising these
results in the text of the Results section, before moving on to discuss the findings
in the Discussion.
A minor observation is that the results focus on both mortality and impairment of
ADL. 
This is not reflected in the title of the paper, or the abstract.
The limitations and strengths section is good.
The conclusion section is good, and this work is novel in that it has identified
that 
location and PPI use are predicators of impairment of ADL.
ADDITIONAL REQUESTS/SUGGESTIONS: 
None , but please see my notes above.
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
Reviewer’s report
Title: 
Risk factors of poor prognosis and impairment of activities of daily living
in patients with hemorrhagic gastroduodenal ulcers
Version: 
0 
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)?
No - there are minor issues
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?
Yes - the author's interpretation is reasonable
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: 
* What is your overall impression of the study?
Interesting with some novel results relevant to care of older people and service
planning.
* What have the authors done well?
Provided an analysis of risk factors for impairment of daily living after
haemorrhagic ulcer, using retrospective methods. Analyses are appropriate. 
* In what ways does it not meet best practice?
The report of the study needs some additional detail and re-organisation of some
of the text to improve readability.
REQUESTED REVISIONS: 
Objective 
- minor issues. 
These are issues of clarity in reporting rather than
conduct of the research, please see my notes about the Abstract and methods, in
particularly the statements concerning specification of the risk factors and the
outcomes of interest 
in the report.
Design 
- minor issues. 
Only in that the study is of retrospective design and in a
single centre, which is discussed in the Discussion section as a potential
limitation.
Execution - appropriate, but some additional detail needs to be given in the
report for clarity.
Statistics - appropriate.
Interpretation - reasonable
Further details are provided below on a section by section basis.
Abstract 
Impairment of activities of daily living (ADL) due to haemorrhagic
gastroduodenal ulcers (HGU) has rarely been evaluated. The Background then
goes on cite several studies in which mortality and hospitalization have ben
studied. It might be better just to state that the authors evaluated Impairment of
activities of daily living (ADL) due to haemorrhagic gastroduodenal ulcer in the
abstract and expand on the lack of data other than mortality, hospitalizations and
healthcare costs in the Background, 
i.e. please make the 
case for the novelty of
this work in the Background section.
State risk factors and outcomes to be evaluated more clearly. 
The retrospective design of this study should be stated in the abstract.
Background.
Please see notes below regarding the choice of risk factors and outcomes. 
The
Background does not state why this research is novel and important for clinical
care and service planning. 
A minor edit to state this clearly would improve the
relevance of the paper.
e.g. 'Although previous studies have evaluated the risk factors for mortality of
HGU, and impairment of ADL has been evaluated in other disease, to date there
have been no studies that have evaluate which risk factors of HGU are
associated with impairment of ADL. 
This is important in both clinical care of
patients who are identified to be at risk of ADL impairment after HGU and for
planning of clinical and social care services. 
This is especially relevant in care of
the elderly since previous reports have revealed that advanced age is a risk factor
of poor outcomes for HGU patients (refs) '
Methods
How was the review conducted - by case notes, how were data extracted, was a
pro forma used and how was this developed (why were the data items chosen)?
Who performed the data extraction? 
How were data stored, collated, verified?
Please provide these details.
Inclusion 
and exclusion criteria. 
Please state these, e.g. co morbidities, residence
in care facilities.
How was ADL assessed? How were these data obtained once the patient had left
hospital care? The paper states that 
"Impairment of ADL was defined as
admission to care facilities after hospital discharge or the requirement of home
modification for rehabilitation at home." However, there is wide variation in
having minor adaptations in the home (which may have been needed for reasons
unrelated to HGU e.g. arthritis, and a full care package delivered in residential
care. This introduces uncertainty in the interpretation authors' of the results for
ADL and at the very least, there should be some discussion of this in the
Discussion section.
State risk factors 
- on reading this section data items are specified but it is not
clear how these were chosen as 'risk factors' (Were these chosen a priori ? ). The
reasons for these choices of risk factor and outcome should be stated in the
methods. 
It seems reasonable to select these risk factors and outcomes of
importance based on what is known from clinical practice, but some background
(with references) and reasons should be provided in the paper. The information is
present in the Background to some extent but there is no logical train of
reasoning between the existing knowledge and risk factors and outcomes chosen.
Some editing of the paper would solve this.
I am glad to see ethical approval stated clearly.
Statistical analysis
Statistics used appear to be appropriate, although a detailed opinion should be
sought from a medical statistician.
OR appears to be appropriate, given that the total number of exposed people is
not available, OR here is used as a measure of the strength of association
between exposure and outcome. Odds however are difficult for non specialists to
use and it would be helpful if there was an interpretation of the results in terms
of 
e.g. 'elderly patients who had pre-existing renal disease were x % more likely
to die within 30 days …'
Results
This section is clear enough, but the presentation of results could be better - at
present the format is rather dense and numerical. 
I accept that that is the nature
of the results, but the message is not easy to determine. A summary paragraph
providing the main results would be helpful, stating the clinical factors from
Table 1 and the results for the main outcomes of interest from Table 2. This
information appears throughout the Discussion and moving does this information
to the Results section would improve the readability.
Tables - all fine - possibly the OR could be plotted rather than being presented as
a table?
It is unclear why patients who resided in care facilities were included in the
initial data analyses, but later excluded. 
Since they were already experiencing
disruption to ADL presumably, these patients should have been excluded and the
inclusion/exclusion criteria should have been stated in the methods section (e.g..
malignancies, pre-existing dementia).
Discussion
The Discussion is good, as each finding is compared and contrasted with what is
already known. 
However please see my note above about summarising these
results in the text of the Results section, before moving on to discuss the findings
in the Discussion.
A minor observation is that the results focus on both mortality and impairment of
ADL. 
This is not reflected in the title of the paper, or the abstract.
The limitations and strengths section is good.
The conclusion section is good, and this work is novel in that it has identified
that 
location and PPI use are predicators of impairment of ADL.
ADDITIONAL REQUESTS/SUGGESTIONS: 
None , but please see my notes above.
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
Please review this paper.
user
Reviewer’s report
Title: 
Risk factors of poor prognosis and impairment of activities of daily living
in patients with hemorrhagic gastroduodenal ulcers
Version: 
0 
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)?
No - there are minor issues
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?
Yes - the author's interpretation is reasonable
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: 
* What is your overall impression of the study?
Interesting with some novel results relevant to care of older people and service
planning.
* What have the authors done well?
Provided an analysis of risk factors for impairment of daily living after
haemorrhagic ulcer, using retrospective methods. Analyses are appropriate. 
* In what ways does it not meet best practice?
The report of the study needs some additional detail and re-organisation of some
of the text to improve readability.
REQUESTED REVISIONS: 
Objective 
- minor issues. 
These are issues of clarity in reporting rather than
conduct of the research, please see my notes about the Abstract and methods, in
particularly the statements concerning specification of the risk factors and the
outcomes of interest 
in the report.
Design 
- minor issues. 
Only in that the study is of retrospective design and in a
single centre, which is discussed in the Discussion section as a potential
limitation.
Execution - appropriate, but some additional detail needs to be given in the
report for clarity.
Statistics - appropriate.
Interpretation - reasonable
Further details are provided below on a section by section basis.
Abstract 
Impairment of activities of daily living (ADL) due to haemorrhagic
gastroduodenal ulcers (HGU) has rarely been evaluated. The Background then
goes on cite several studies in which mortality and hospitalization have ben
studied. It might be better just to state that the authors evaluated Impairment of
activities of daily living (ADL) due to haemorrhagic gastroduodenal ulcer in the
abstract and expand on the lack of data other than mortality, hospitalizations and
healthcare costs in the Background, 
i.e. please make the 
case for the novelty of
this work in the Background section.
State risk factors and outcomes to be evaluated more clearly. 
The retrospective design of this study should be stated in the abstract.
Background.
Please see notes below regarding the choice of risk factors and outcomes. 
The
Background does not state why this research is novel and important for clinical
care and service planning. 
A minor edit to state this clearly would improve the
relevance of the paper.
e.g. 'Although previous studies have evaluated the risk factors for mortality of
HGU, and impairment of ADL has been evaluated in other disease, to date there
have been no studies that have evaluate which risk factors of HGU are
associated with impairment of ADL. 
This is important in both clinical care of
patients who are identified to be at risk of ADL impairment after HGU and for
planning of clinical and social care services. 
This is especially relevant in care of
the elderly since previous reports have revealed that advanced age is a risk factor
of poor outcomes for HGU patients (refs) '
Methods
How was the review conducted - by case notes, how were data extracted, was a
pro forma used and how was this developed (why were the data items chosen)?
Who performed the data extraction? 
How were data stored, collated, verified?
Please provide these details.
Inclusion 
and exclusion criteria. 
Please state these, e.g. co morbidities, residence
in care facilities.
How was ADL assessed? How were these data obtained once the patient had left
hospital care? The paper states that 
"Impairment of ADL was defined as
admission to care facilities after hospital discharge or the requirement of home
modification for rehabilitation at home." However, there is wide variation in
having minor adaptations in the home (which may have been needed for reasons
unrelated to HGU e.g. arthritis, and a full care package delivered in residential
care. This introduces uncertainty in the interpretation authors' of the results for
ADL and at the very least, there should be some discussion of this in the
Discussion section.
State risk factors 
- on reading this section data items are specified but it is not
clear how these were chosen as 'risk factors' (Were these chosen a priori ? ). The
reasons for these choices of risk factor and outcome should be stated in the
methods. 
It seems reasonable to select these risk factors and outcomes of
importance based on what is known from clinical practice, but some background
(with references) and reasons should be provided in the paper. The information is
present in the Background to some extent but there is no logical train of
reasoning between the existing knowledge and risk factors and outcomes chosen.
Some editing of the paper would solve this.
I am glad to see ethical approval stated clearly.
Statistical analysis
Statistics used appear to be appropriate, although a detailed opinion should be
sought from a medical statistician.
OR appears to be appropriate, given that the total number of exposed people is
not available, OR here is used as a measure of the strength of association
between exposure and outcome. Odds however are difficult for non specialists to
use and it would be helpful if there was an interpretation of the results in terms
of 
e.g. 'elderly patients who had pre-existing renal disease were x % more likely
to die within 30 days …'
Results
This section is clear enough, but the presentation of results could be better - at
present the format is rather dense and numerical. 
I accept that that is the nature
of the results, but the message is not easy to determine. A summary paragraph
providing the main results would be helpful, stating the clinical factors from
Table 1 and the results for the main outcomes of interest from Table 2. This
information appears throughout the Discussion and moving does this information
to the Results section would improve the readability.
Tables - all fine - possibly the OR could be plotted rather than being presented as
a table?
It is unclear why patients who resided in care facilities were included in the
initial data analyses, but later excluded. 
Since they were already experiencing
disruption to ADL presumably, these patients should have been excluded and the
inclusion/exclusion criteria should have been stated in the methods section (e.g..
malignancies, pre-existing dementia).
Discussion
The Discussion is good, as each finding is compared and contrasted with what is
already known. 
However please see my note above about summarising these
results in the text of the Results section, before moving on to discuss the findings
in the Discussion.
A minor observation is that the results focus on both mortality and impairment of
ADL. 
This is not reflected in the title of the paper, or the abstract.
The limitations and strengths section is good.
The conclusion section is good, and this work is novel in that it has identified
that 
location and PPI use are predicators of impairment of ADL.
ADDITIONAL REQUESTS/SUGGESTIONS: 
None , but please see my notes above.
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
assistant