Title: Health-care resource use and costs associated with inflammatory bowel disease in
northwest London: a retrospective linked database study
Version: 0 Date: 09 Nov 2024
Reviewer's report:
This is an interesting article which highlights aspects of the cost of IBD not previously reported
from the UK. By analyzing real data, the authors avoid the speculation of cost-modelling in
previous UK publications.
The data are well presented overall.
I would suggest more attention to the following issues:
Page 3: "Biosimilars are 70% less expensive." Is this really true in the UK?
Disease definition in a database: Please related to the possibility of error of diagnosis. Also, did
the authors check for a change of diagnosis?
I did not understand the statement that half were diagnosed 2 years or longer (page 6). What was
the requirement for inclusion. Was a single record in the database sufficient?
Unlike other publications, the percentage of persons in remission is very high. How is this
possible?
The cohort of UC was essentially composed of older people, unlike CT or undefined. Please
comment.
In 50% the ethnicity was unknown. Please comment.
Smoking was not reported. Is this not part of the NHS database?
Time since diagnosis was not given (or did I miss this?).
The cost per patient data: Is this per year? Per period?
The labelling should be consistent in all the graphs.  The reader cannot be expected to refer to
previous graphs to understand all items.
References: These are obviously the prerogative of the authors. However, I would like to point
out that ref. 38 refers to children. Furthermore, the authors' work would be more relevant if
it were compared with the landmark studies of other groups reported in the literature, such as
Burisch et al. in Lancet Gastroenterology Hepatology 2020 and2023.
Title: Health-care resource use and costs associated with inflammatory bowel disease in
northwest London: a retrospective linked database study
Version: 0 Date: 09 Nov 2024
Reviewer's report:
This is an interesting article which highlights aspects of the cost of IBD not previously reported
from the UK. By analyzing real data, the authors avoid the speculation of cost-modelling in
previous UK publications.
The data are well presented overall.
I would suggest more attention to the following issues:
Page 3: "Biosimilars are 70% less expensive." Is this really true in the UK?
Disease definition in a database: Please related to the possibility of error of diagnosis. Also, did
the authors check for a change of diagnosis?
I did not understand the statement that half were diagnosed 2 years or longer (page 6). What was
the requirement for inclusion. Was a single record in the database sufficient?
Unlike other publications, the percentage of persons in remission is very high. How is this
possible?
The cohort of UC was essentially composed of older people, unlike CT or undefined. Please
comment.
In 50% the ethnicity was unknown. Please comment.
Smoking was not reported. Is this not part of the NHS database?
Time since diagnosis was not given (or did I miss this?).
The cost per patient data: Is this per year? Per period?
The labelling should be consistent in all the graphs.  The reader cannot be expected to refer to
previous graphs to understand all items.
References: These are obviously the prerogative of the authors. However, I would like to point
out that ref. 38 refers to children. Furthermore, the authors' work would be more relevant if
it were compared with the landmark studies of other groups reported in the literature, such as
Burisch et al. in Lancet Gastroenterology Hepatology 2020 and2023.
Please review this paper.
user
Title: Health-care resource use and costs associated with inflammatory bowel disease in
northwest London: a retrospective linked database study
Version: 0 Date: 09 Nov 2024
Reviewer's report:
This is an interesting article which highlights aspects of the cost of IBD not previously reported
from the UK. By analyzing real data, the authors avoid the speculation of cost-modelling in
previous UK publications.
The data are well presented overall.
I would suggest more attention to the following issues:
Page 3: "Biosimilars are 70% less expensive." Is this really true in the UK?
Disease definition in a database: Please related to the possibility of error of diagnosis. Also, did
the authors check for a change of diagnosis?
I did not understand the statement that half were diagnosed 2 years or longer (page 6). What was
the requirement for inclusion. Was a single record in the database sufficient?
Unlike other publications, the percentage of persons in remission is very high. How is this
possible?
The cohort of UC was essentially composed of older people, unlike CT or undefined. Please
comment.
In 50% the ethnicity was unknown. Please comment.
Smoking was not reported. Is this not part of the NHS database?
Time since diagnosis was not given (or did I miss this?).
The cost per patient data: Is this per year? Per period?
The labelling should be consistent in all the graphs.  The reader cannot be expected to refer to
previous graphs to understand all items.
References: These are obviously the prerogative of the authors. However, I would like to point
out that ref. 38 refers to children. Furthermore, the authors' work would be more relevant if
it were compared with the landmark studies of other groups reported in the literature, such as
Burisch et al. in Lancet Gastroenterology Hepatology 2020 and2023.
assistant