Round 1

Reviewer 1 Report

The research paper of Allegra Ferrari et al. entitled "Differences and similarities in breast and colorectal cancer screening uptake among municipalities in Flanders, Belgium" is an informative study which aims to provide an insight on municipal level determinants of screening participation in the target population for both BC and CRC. However, there are several minor issues of this study.

1. The Tables are too many in this manuscript. Tables 1,2 are redundant and would be better included as supplemental materials.
2. The Discussion is very lengthy and includes too many details. The Authors are advised to be more careful in the content and more focused on the most important parts of their study.
3. Additional commentary could be added in the Discussion, regarding the importance of the findings and their potential utilization into standard clinical practice.
4. Proofreading of the manuscript is needed, since there are some syntax and grammar errors.

Author Response

Dear Editors and Reviewers,

Re: [GastrointestDisord] Manuscript ID: gastrointestdisord-1642644: Differences and similarities in breast and colorectal cancer screening uptake among municipalities in Flanders, Belgium

We would like to thank the reviewers and the editorial board for their time spent in reviewing our manuscript. We are delighted to have the opportunity to revise the manuscript in light of the comments and suggestions provided. We believe we have now adequately addressed all the comments as itemized in our point-by-point reply below. For your convenience, all changes are marked up using “track changes” in our revised manuscript. We also added Mathieu Goossens as a co-author. Being the programme manager of the Flemish Breast Cancer Screening programme, he was involved in our study but due to a misunderstanding, he was not included as a co-author in the first version.

Sincerely

Guido Van Hal

on behalf of the authors

Reviewer 1

Comments and Suggestions for Authors

The research paper of Allegra Ferrari et al. entitled "Differences and similarities in breast and colorectal cancer screening uptake among municipalities in Flanders, Belgium" is an informative study which aims to provide an insight on municipal level determinants of screening participation in the target population for both BC and CRC. However, there are several minor issues of this study.

Point 1

• The Tables are too many in this manuscript. Tables 1,2 are redundant and would be better included as supplemental materials.
  
  
• Thank you for this suggestion. We have now moved Tables 1 and 2 (now Tables S1 and S2) in the Supplementary Material. As a consequence, we have modified the Methods section 2.3 as follows:

Fourteen demographic, socioeconomic and health-related municipal parameters were investigated as potential factors associated with BC and CRC screening uptake. These were, respectively:

• Age group (group 1: people aged between 55 and 59 years old; group 2: people aged between 60 and 64 years old; group 3: people aged between 65 and 69 years old), Average household size (n.), Residential stability (Same Address), Having a partner, Having children, Foreign Nationality;
• Average income (EUR), Position in the labor market (Jobseekers, Wage earners, Self-employed, (Early) retired), Students in Higher education;
• Chronic Conditions, Diabetes, Disabilities, General practitioner (GP) visits, Preventive Dental visits;

With the exception of “Average household size” and “Average income”, all listed variables were expressed as rates. These were measured over the total population (both males and females) of each municipality and were used as a proxy for the characteristics of the female target population.  Instead, the rates of each age group were calculated exclusively over the female target population. 
Because of the substantial cultural and linguistic similarities between Belgium and the Netherlands (being Dutch the official Flemish language), people without either of these nationalities were referred to as foreigners. 
Within each municipality, the percentage of residents aged 18–24 studying at a college/university (higher education) was used as a proxy for education level. Additional details on the included variables are available in Supplementary Material (Table S1) and online at https://provincies.incijfers.be/databank (Accessed on 1 February 2021).

(Lines 112-135)

Point 2

• The Discussion is very lengthy and includes too many details. The Authors are advised to be more careful in the content and more focused on the most important parts of their study. Additional commentary could be added in the Discussion, regarding the importance of the findings and their potential utilization into standard clinical practice.

• Following the Reviewer’s suggestion, we have shortened the discussion where possible. We believe that, by making small changes in the phrasing (lines 373, 384-386, 388, 392, 473) we have now posed higher emphasis on the most important results of the study.
  In addition, by modifying both Discussion and Conclusions we have now implemented the text with regards to the potential utilization of our findings in clinical practice:
  
  - Discussion (lines 478-508)

Retrieved data should be used to tailor interventions with the intent of improving knowledge about the importance of early detection of both BC and CRC and increase screening uptake, particularly among women presenting with the characteristics which are common within municipalities that perform worse in terms of BC and CRC screening uptake. For example, given that foreign nationality has been found to be associated with lower screening uptake, it is important to be mindful of the possible cultural and language barriers which may exist within our target population and therefore attempt to tailor invitation letters and informative content to these needs.

In addition, it is important to actively ensure that the presence of any pre-existing condition (older age, having diabetes, having a disability) does not overshadow the importance of preventative screening. In this regard, it is imperative to reduce healthcare access barriers and facilitate communications between patients and healthcare providers. GPs, in particular, should remain up to date regarding the need for cancer screening and should be given the tools with which to promote screening adherence among their patients.

- Conclusions (lines 511-518)

The present study was the first to compare CRC and BC screening uptake in a target population for both screenings in Flanders. Collected evidence allows for a better identification of those members of the community (both providers and patients) towards which it is especially crucial to tailor interventions and raise awareness about the importance of early cancer detection within the organized screening programs.

In addition, this study allowed us to explore not only the existing interrelationships between the two programs, but also geographical differences in screening participation patterns in Flanders. Further studies are needed to identify the social and cultural roots of these differences as well as possible intervention measures.

Point 3

• Proofreading of the manuscript is needed, since there are some syntax and grammar errors.

• Thank you for pointing this out. We have now performed a full syntax and grammar check and modified the text accordingly.

Reviewer 2 Report

It was a pleasure to revise this paper.
The paper is well written and the conclusions are supported by the results presented. Some bibliographic citations dating back to the 1990s should be replaced by more recent ones. The English language requires minor revision for some typos.

Author Response

Dear Editors and Reviewers,

Re: [GastrointestDisord] Manuscript ID: gastrointestdisord-1642644: Differences and similarities in breast and colorectal cancer screening uptake among municipalities in Flanders, Belgium

We would like to thank the reviewers and the editorial board for their time spent in reviewing our manuscript. We are delighted to have the opportunity to revise the manuscript in light of the comments and suggestions provided. We believe we have now adequately addressed all the comments as itemized in our point-by-point reply below. For your convenience, all changes are marked up using “track changes” in our revised manuscript. We also added Mathieu Goossens as a co-author. Being the programme manager of the Flemish Breast Cancer Screening programme, he was involved in our study but due to a misunderstanding, he was not included as a co-author in the first version.

Sincerely

Guido Van Hal

on behalf of the authors

Reviewer 2

Comments and Suggestions for Authors

It was a pleasure to revise this paper. The paper is well written and the conclusions are supported by the results presented.

Point 1

• Some bibliographic citations dating back to the 1990s should be replaced by more recent ones.
  
  
• Thank you for the suggestion. Accordingly, we have now replaced the reference “Freedman, D. A. Ecological Inference and the Ecological Fallacy. Prepared for the International Encyclopedia of the Social & Behavioral Sciences Technical Report No. 549 (1999)” with “ Sedgwick, Philip. «Ecological Studies: Advantages and Disadvantages». BMJ. 2014, 348 (g2979). https://doi.org/10.1136/bmj.g2979“ (Lines 671-672).

Point 2

• The English language requires minor revision for some typos.

• Following the reviewer recommendation we have now performed a full syntax and grammar check and modified the text accordingly.