Title: Serrated polyposis syndrome: defining the epidemiology and predicting the risk of
dysplasia
Version: 1 Date: 07 Dec 2023
Reviewer's report:
The manuscript entitled “Serrated polyposis syndrome: defining the epidemiology and
predicting the risk of dysplasia” utilizes data from a regional Australian single-centre setting
and includes 247 patients with serrated polyposis syndrome. The authors conclude that serrated
polyposis syndrome is more common than previously though and that they have been able
to develop a prediction model with acceptable accuracy. Unfortunately, the manuscript has
substantial methodological limitations, of which a few is listed below:
1. The study period is from 2015-2021. It seems that information from before 2015 is actually
included if available for subjects undergoing colonoscopy in the study period. It is unclear how
subjects with several colonoscopies during the study period are dealt with. Are the subjects
included multiple times in the project?
2. Since the study is mostly cross sectional (but likely a combination of both cross sectional and
longitudinal data as indicated above), generalizability is prevented. These findings cannot be
replicated in other settings since there are no clear time for inclusion in the “cohort”. In addition,
the “cohort” is a mix of various different indications for colonoscopy.
3. The diagnosis of serrated polyposis syndrome can only be made after histological
examination. Hence, there is no clinical value in “predicting” dysplasia in this setting since this
diagnosis is made exactly at the same time as the diagnosis of serrated polyposis syndrome for
the majority of patients.
4. In figure 1, what is meant by “loss to follow-up”? There is no follow-up for the majority of
patients (this is primarily a cross-sectional study). If there is follow-up available, the authors
need to define start of follow-up and describe follow-up time. And if patients fulfill the criteria
for serrated polyposis syndrome before study start in 2015, they cannot be included since they
do not contribute risk time.
5. In the abstract, it is stated that 8401 patients underwent colonoscopy screening, but this not
correct according to the manuscript. Included patients represent a mix of various indications for
colonoscopy.
6. What is meant by “define the epidemiology” of serrated polyposis syndrome? This is a very
unspecific term.
Title: Serrated polyposis syndrome: defining the epidemiology and predicting the risk of
dysplasia
Version: 1 Date: 07 Dec 2023
Reviewer's report:
The manuscript entitled “Serrated polyposis syndrome: defining the epidemiology and
predicting the risk of dysplasia” utilizes data from a regional Australian single-centre setting
and includes 247 patients with serrated polyposis syndrome. The authors conclude that serrated
polyposis syndrome is more common than previously though and that they have been able
to develop a prediction model with acceptable accuracy. Unfortunately, the manuscript has
substantial methodological limitations, of which a few is listed below:
1. The study period is from 2015-2021. It seems that information from before 2015 is actually
included if available for subjects undergoing colonoscopy in the study period. It is unclear how
subjects with several colonoscopies during the study period are dealt with. Are the subjects
included multiple times in the project?
2. Since the study is mostly cross sectional (but likely a combination of both cross sectional and
longitudinal data as indicated above), generalizability is prevented. These findings cannot be
replicated in other settings since there are no clear time for inclusion in the “cohort”. In addition,
the “cohort” is a mix of various different indications for colonoscopy.
3. The diagnosis of serrated polyposis syndrome can only be made after histological
examination. Hence, there is no clinical value in “predicting” dysplasia in this setting since this
diagnosis is made exactly at the same time as the diagnosis of serrated polyposis syndrome for
the majority of patients.
4. In figure 1, what is meant by “loss to follow-up”? There is no follow-up for the majority of
patients (this is primarily a cross-sectional study). If there is follow-up available, the authors
need to define start of follow-up and describe follow-up time. And if patients fulfill the criteria
for serrated polyposis syndrome before study start in 2015, they cannot be included since they
do not contribute risk time.
5. In the abstract, it is stated that 8401 patients underwent colonoscopy screening, but this not
correct according to the manuscript. Included patients represent a mix of various indications for
colonoscopy.
6. What is meant by “define the epidemiology” of serrated polyposis syndrome? This is a very
unspecific term.
Please review this paper.
user
Title: Serrated polyposis syndrome: defining the epidemiology and predicting the risk of
dysplasia
Version: 1 Date: 07 Dec 2023
Reviewer's report:
The manuscript entitled “Serrated polyposis syndrome: defining the epidemiology and
predicting the risk of dysplasia” utilizes data from a regional Australian single-centre setting
and includes 247 patients with serrated polyposis syndrome. The authors conclude that serrated
polyposis syndrome is more common than previously though and that they have been able
to develop a prediction model with acceptable accuracy. Unfortunately, the manuscript has
substantial methodological limitations, of which a few is listed below:
1. The study period is from 2015-2021. It seems that information from before 2015 is actually
included if available for subjects undergoing colonoscopy in the study period. It is unclear how
subjects with several colonoscopies during the study period are dealt with. Are the subjects
included multiple times in the project?
2. Since the study is mostly cross sectional (but likely a combination of both cross sectional and
longitudinal data as indicated above), generalizability is prevented. These findings cannot be
replicated in other settings since there are no clear time for inclusion in the “cohort”. In addition,
the “cohort” is a mix of various different indications for colonoscopy.
3. The diagnosis of serrated polyposis syndrome can only be made after histological
examination. Hence, there is no clinical value in “predicting” dysplasia in this setting since this
diagnosis is made exactly at the same time as the diagnosis of serrated polyposis syndrome for
the majority of patients.
4. In figure 1, what is meant by “loss to follow-up”? There is no follow-up for the majority of
patients (this is primarily a cross-sectional study). If there is follow-up available, the authors
need to define start of follow-up and describe follow-up time. And if patients fulfill the criteria
for serrated polyposis syndrome before study start in 2015, they cannot be included since they
do not contribute risk time.
5. In the abstract, it is stated that 8401 patients underwent colonoscopy screening, but this not
correct according to the manuscript. Included patients represent a mix of various indications for
colonoscopy.
6. What is meant by “define the epidemiology” of serrated polyposis syndrome? This is a very
unspecific term.
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