Title: COVID-19 Vaccination Safety and associated Health Care Utilization among Adults with
Inflammatory Bowel Disease – A population-based self-controlled case series analysis
Version: 1 Date: 23 Mar 2024
Reviewer's report:
Overall interesting paper on COVID-19 vaccination safety employing a self-controlled case
series which has been previously used in vaccine safety studies. Please find my comments to
the authors below.
1) I think it would be useful to describe the self-controlled case series analysis in a bit more
detail in the materials and methods section.
2) Secondary outcomes studies included IBD-related visits. As mentioned on the material and
methods section, those were defined by either a diagnostic code specific for IBD, or codes related
to signs, symptoms and EIM of IBD. However, looking through the supplementary tables, it
looks like there were codes included that are not necessarily related to IBD such as dysphagia,
peptic ulcer etc. Can the authors please comment on that and how this might have affected results.
3) Could the authors please comment on the use of standardized difference and not p-values for
comparisons between IBD and non-IBD populations. This needs to be described in methods too.
4) Finally, I think all tables of the paper need to be reformed. Their current size seems too big.
Plus tables 2,3 and 4 include a section combining all cause hospitalization and ED visits which
I think could be moved to supplementary material as these results are not mentioned at all in
the results section.
Title: COVID-19 Vaccination Safety and associated Health Care Utilization among Adults with
Inflammatory Bowel Disease – A population-based self-controlled case series analysis
Version: 1 Date: 23 Mar 2024
Reviewer's report:
Overall interesting paper on COVID-19 vaccination safety employing a self-controlled case
series which has been previously used in vaccine safety studies. Please find my comments to
the authors below.
1) I think it would be useful to describe the self-controlled case series analysis in a bit more
detail in the materials and methods section.
2) Secondary outcomes studies included IBD-related visits. As mentioned on the material and
methods section, those were defined by either a diagnostic code specific for IBD, or codes related
to signs, symptoms and EIM of IBD. However, looking through the supplementary tables, it
looks like there were codes included that are not necessarily related to IBD such as dysphagia,
peptic ulcer etc. Can the authors please comment on that and how this might have affected results.
3) Could the authors please comment on the use of standardized difference and not p-values for
comparisons between IBD and non-IBD populations. This needs to be described in methods too.
4) Finally, I think all tables of the paper need to be reformed. Their current size seems too big.
Plus tables 2,3 and 4 include a section combining all cause hospitalization and ED visits which
I think could be moved to supplementary material as these results are not mentioned at all in
the results section.
Please review this paper.
user
Title: COVID-19 Vaccination Safety and associated Health Care Utilization among Adults with
Inflammatory Bowel Disease – A population-based self-controlled case series analysis
Version: 1 Date: 23 Mar 2024
Reviewer's report:
Overall interesting paper on COVID-19 vaccination safety employing a self-controlled case
series which has been previously used in vaccine safety studies. Please find my comments to
the authors below.
1) I think it would be useful to describe the self-controlled case series analysis in a bit more
detail in the materials and methods section.
2) Secondary outcomes studies included IBD-related visits. As mentioned on the material and
methods section, those were defined by either a diagnostic code specific for IBD, or codes related
to signs, symptoms and EIM of IBD. However, looking through the supplementary tables, it
looks like there were codes included that are not necessarily related to IBD such as dysphagia,
peptic ulcer etc. Can the authors please comment on that and how this might have affected results.
3) Could the authors please comment on the use of standardized difference and not p-values for
comparisons between IBD and non-IBD populations. This needs to be described in methods too.
4) Finally, I think all tables of the paper need to be reformed. Their current size seems too big.
Plus tables 2,3 and 4 include a section combining all cause hospitalization and ED visits which
I think could be moved to supplementary material as these results are not mentioned at all in
the results section.
assistant