Title: Effect of clinical vs. administrative data definitions on the epidemiology of C. difficile
among hospitalized individuals with IBD: A population-based cohort study
Version: 1 Date: 14 Dec 2021
Reviewer's report:
This is an interesting original article about the “Effect of clinical vs. administrative data
definitions on the epidemiology of C. difficile among hospitalized individuals with IBD: A
population-based cohort study „
There are some formal requirements that need to be corrected:
1. There are a few typo, please revise and correct them.
2. Please check the reference rules and correct them accordingly.
3. Please use the official format the journal requested in the abstract:
Background, Methods, Results, Conclusions
I have a few points according to the article:
1. Please consider to relocate the last sentence of the introduction to the methods.
2. Please help me clear what was the matching system.
• on page 8th and 10th:  “Cases of IBD in the UMIBDED, (as of March 2015, n=8,277), are
matched 1:10 to age, sex and area of residence (at time of IBD diagnosis) matched controls
(n=72,387).” „The UMIBDED (April 1, 1984 – March 31, 2014) was used to identify individuals
with IBD, who were matched 1: 10 to those without IBD on age, sex, and area of residence (at
IBD diagnosis/ index date).”
• on page 10th: “Each individual with IBD with CDI diagnosis during a hospitalization was
matched with four IBD cases without a hospital record of CDI on or prior to the CDI index date
(hospital admission date for first hospitalization with CDI), according to IBD type (UC vs. CD),
gender, year of IBD diagnosis, and age.“
Why is it relevant in this study how in the UMIBDED database are the patients matched with
non-IBD patients?
3. on the page 12: “and a non-statistically significant decrease based on the DAD (APC=-4.7%,
95% CI -10.6, 1.7, P=0.12).”  - It would be better to say statistically non-significant but strong
tendency of decreasing…
4. Im suggesting to use the supplementary figure 1 as one of the main figure.
5. Is there a data about the concordance between the 108 lab and the 110 DAD patient? Were
they the same patients?
6. the discussion is too long
Title: Effect of clinical vs. administrative data definitions on the epidemiology of C. difficile
among hospitalized individuals with IBD: A population-based cohort study
Version: 1 Date: 14 Dec 2021
Reviewer's report:
This is an interesting original article about the “Effect of clinical vs. administrative data
definitions on the epidemiology of C. difficile among hospitalized individuals with IBD: A
population-based cohort study „
There are some formal requirements that need to be corrected:
1. There are a few typo, please revise and correct them.
2. Please check the reference rules and correct them accordingly.
3. Please use the official format the journal requested in the abstract:
Background, Methods, Results, Conclusions
I have a few points according to the article:
1. Please consider to relocate the last sentence of the introduction to the methods.
2. Please help me clear what was the matching system.
• on page 8th and 10th:  “Cases of IBD in the UMIBDED, (as of March 2015, n=8,277), are
matched 1:10 to age, sex and area of residence (at time of IBD diagnosis) matched controls
(n=72,387).” „The UMIBDED (April 1, 1984 – March 31, 2014) was used to identify individuals
with IBD, who were matched 1: 10 to those without IBD on age, sex, and area of residence (at
IBD diagnosis/ index date).”
• on page 10th: “Each individual with IBD with CDI diagnosis during a hospitalization was
matched with four IBD cases without a hospital record of CDI on or prior to the CDI index date
(hospital admission date for first hospitalization with CDI), according to IBD type (UC vs. CD),
gender, year of IBD diagnosis, and age.“
Why is it relevant in this study how in the UMIBDED database are the patients matched with
non-IBD patients?
3. on the page 12: “and a non-statistically significant decrease based on the DAD (APC=-4.7%,
95% CI -10.6, 1.7, P=0.12).”  - It would be better to say statistically non-significant but strong
tendency of decreasing…
4. Im suggesting to use the supplementary figure 1 as one of the main figure.
5. Is there a data about the concordance between the 108 lab and the 110 DAD patient? Were
they the same patients?
6. the discussion is too long
Please review this paper.
user
Title: Effect of clinical vs. administrative data definitions on the epidemiology of C. difficile
among hospitalized individuals with IBD: A population-based cohort study
Version: 1 Date: 14 Dec 2021
Reviewer's report:
This is an interesting original article about the “Effect of clinical vs. administrative data
definitions on the epidemiology of C. difficile among hospitalized individuals with IBD: A
population-based cohort study „
There are some formal requirements that need to be corrected:
1. There are a few typo, please revise and correct them.
2. Please check the reference rules and correct them accordingly.
3. Please use the official format the journal requested in the abstract:
Background, Methods, Results, Conclusions
I have a few points according to the article:
1. Please consider to relocate the last sentence of the introduction to the methods.
2. Please help me clear what was the matching system.
• on page 8th and 10th:  “Cases of IBD in the UMIBDED, (as of March 2015, n=8,277), are
matched 1:10 to age, sex and area of residence (at time of IBD diagnosis) matched controls
(n=72,387).” „The UMIBDED (April 1, 1984 – March 31, 2014) was used to identify individuals
with IBD, who were matched 1: 10 to those without IBD on age, sex, and area of residence (at
IBD diagnosis/ index date).”
• on page 10th: “Each individual with IBD with CDI diagnosis during a hospitalization was
matched with four IBD cases without a hospital record of CDI on or prior to the CDI index date
(hospital admission date for first hospitalization with CDI), according to IBD type (UC vs. CD),
gender, year of IBD diagnosis, and age.“
Why is it relevant in this study how in the UMIBDED database are the patients matched with
non-IBD patients?
3. on the page 12: “and a non-statistically significant decrease based on the DAD (APC=-4.7%,
95% CI -10.6, 1.7, P=0.12).”  - It would be better to say statistically non-significant but strong
tendency of decreasing…
4. Im suggesting to use the supplementary figure 1 as one of the main figure.
5. Is there a data about the concordance between the 108 lab and the 110 DAD patient? Were
they the same patients?
6. the discussion is too long
assistant