Title: Effectiveness of switching endoscopists for repeat surveillance colonoscopy: a
retrospective study
Version: 0 Date: 03 Jul 2023
Reviewer's report:
In the present report, the authors presented "Effectiveness of switching endoscopists for repeat
surveillance colonoscopy: a retrospective study". The topic of this study is novel and interesting.
However, there are significant biases in this paper. And there are some parts that should be
explained in more detail in the method section.
Major points
1. There were significant differences in the rate of high-resolution scope, the pattern of scope
change, the rate of trainees, and other backgrounds between S group and D group. These could
significantly affect all analyses. Authors should match the backgrounds of the two groups. If
this is not possible, please explain and discuss this in the Discussion section.
2. Were there any rules for determining two groups? Because there were many differences
between two groups. What about diversity of endoscopists? Authors should report the number
of endoscopists in each group.
3. I am concerned about the evaluation of missed polyps. If there are 10 small polyps for CSP and
1 large lesion for EMR in a first colonoscopy, some of the small polyps may be left for the next
EMR according to time limitation for outpatient. In this situation, how do authors differentiate
missed polyps from previously detected polyps? Because the appearance of some small polyps
seems similar and it is difficult to differentiate them.
Minor points
4. Authors presented "The presence of PCCRCs may indicate that the ADR may be inadequate
in terms of its limited value in assessing the number of detected adenomas and missed lesions
[6]" in the Introduction section. The meaning of this sentence is unclear. The authors should
revise this.
5. Regarding exclusion, "inability to evaluate all polyps" in Figure 1 is unclear. Please explain
this in the main text.
6. This study was a retrospective setting. How did the author calculate the withdrawal time for
observation only?
7. Authors should calculate P-value about age, sex and other factors between two groups in
Table 1.
8. Some endoscopists use NBI for routine colonoscopy to improve polyp detection. In this study,
was the whole colon examined by white light imaging only? Please report this in the Methods
section.
9. The authors should analyze the results not only for trainees but also for experts. How about
classifying all endoscopists into three groups (experts, non-experts, trainees)?
10. Authors should explain histopathologic evaluation in this study. According to the definition
of histopathology in this study, SSA/P can be replaced by SSL in Table 3.
Title: Effectiveness of switching endoscopists for repeat surveillance colonoscopy: a
retrospective study
Version: 0 Date: 03 Jul 2023
Reviewer's report:
In the present report, the authors presented "Effectiveness of switching endoscopists for repeat
surveillance colonoscopy: a retrospective study". The topic of this study is novel and interesting.
However, there are significant biases in this paper. And there are some parts that should be
explained in more detail in the method section.
Major points
1. There were significant differences in the rate of high-resolution scope, the pattern of scope
change, the rate of trainees, and other backgrounds between S group and D group. These could
significantly affect all analyses. Authors should match the backgrounds of the two groups. If
this is not possible, please explain and discuss this in the Discussion section.
2. Were there any rules for determining two groups? Because there were many differences
between two groups. What about diversity of endoscopists? Authors should report the number
of endoscopists in each group.
3. I am concerned about the evaluation of missed polyps. If there are 10 small polyps for CSP and
1 large lesion for EMR in a first colonoscopy, some of the small polyps may be left for the next
EMR according to time limitation for outpatient. In this situation, how do authors differentiate
missed polyps from previously detected polyps? Because the appearance of some small polyps
seems similar and it is difficult to differentiate them.
Minor points
4. Authors presented "The presence of PCCRCs may indicate that the ADR may be inadequate
in terms of its limited value in assessing the number of detected adenomas and missed lesions
[6]" in the Introduction section. The meaning of this sentence is unclear. The authors should
revise this.
5. Regarding exclusion, "inability to evaluate all polyps" in Figure 1 is unclear. Please explain
this in the main text.
6. This study was a retrospective setting. How did the author calculate the withdrawal time for
observation only?
7. Authors should calculate P-value about age, sex and other factors between two groups in
Table 1.
8. Some endoscopists use NBI for routine colonoscopy to improve polyp detection. In this study,
was the whole colon examined by white light imaging only? Please report this in the Methods
section.
9. The authors should analyze the results not only for trainees but also for experts. How about
classifying all endoscopists into three groups (experts, non-experts, trainees)?
10. Authors should explain histopathologic evaluation in this study. According to the definition
of histopathology in this study, SSA/P can be replaced by SSL in Table 3.
Please review this paper.
user
Title: Effectiveness of switching endoscopists for repeat surveillance colonoscopy: a
retrospective study
Version: 0 Date: 03 Jul 2023
Reviewer's report:
In the present report, the authors presented "Effectiveness of switching endoscopists for repeat
surveillance colonoscopy: a retrospective study". The topic of this study is novel and interesting.
However, there are significant biases in this paper. And there are some parts that should be
explained in more detail in the method section.
Major points
1. There were significant differences in the rate of high-resolution scope, the pattern of scope
change, the rate of trainees, and other backgrounds between S group and D group. These could
significantly affect all analyses. Authors should match the backgrounds of the two groups. If
this is not possible, please explain and discuss this in the Discussion section.
2. Were there any rules for determining two groups? Because there were many differences
between two groups. What about diversity of endoscopists? Authors should report the number
of endoscopists in each group.
3. I am concerned about the evaluation of missed polyps. If there are 10 small polyps for CSP and
1 large lesion for EMR in a first colonoscopy, some of the small polyps may be left for the next
EMR according to time limitation for outpatient. In this situation, how do authors differentiate
missed polyps from previously detected polyps? Because the appearance of some small polyps
seems similar and it is difficult to differentiate them.
Minor points
4. Authors presented "The presence of PCCRCs may indicate that the ADR may be inadequate
in terms of its limited value in assessing the number of detected adenomas and missed lesions
[6]" in the Introduction section. The meaning of this sentence is unclear. The authors should
revise this.
5. Regarding exclusion, "inability to evaluate all polyps" in Figure 1 is unclear. Please explain
this in the main text.
6. This study was a retrospective setting. How did the author calculate the withdrawal time for
observation only?
7. Authors should calculate P-value about age, sex and other factors between two groups in
Table 1.
8. Some endoscopists use NBI for routine colonoscopy to improve polyp detection. In this study,
was the whole colon examined by white light imaging only? Please report this in the Methods
section.
9. The authors should analyze the results not only for trainees but also for experts. How about
classifying all endoscopists into three groups (experts, non-experts, trainees)?
10. Authors should explain histopathologic evaluation in this study. According to the definition
of histopathology in this study, SSA/P can be replaced by SSL in Table 3.
assistant