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Article

Impact of a Failsafe Reminder Letter and Associated Factors on Correct Follow-Up After a Positive FIT in the Flemish Colorectal Cancer Screening Program

by
Sarah Hoeck
1,2,* and
Thuy Ngan Tran
1,2
1
Centre for Cancer Detection, 8000 Bruges, Belgium
2
Social Epidemiology and Health Policy, Family Medicine and Population Health (FAMPOP), University of Antwerp, 2610 Antwerp, Belgium
*
Author to whom correspondence should be addressed.
Gastrointest. Disord. 2025, 7(4), 61; https://doi.org/10.3390/gidisord7040061
Submission received: 24 July 2025 / Revised: 12 September 2025 / Accepted: 23 September 2025 / Published: 26 September 2025
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Abstract

Background: Timely diagnostic colonoscopy (DC) after a positive fecal immunochemical test (FIT+) is essential for effective colorectal cancer (CRC) screening. In Flanders, 16% of FIT+ participants in 2022 had no DC in the 24 months following the FIT+ result. This study evaluated the impact of a failsafe reminder letter—sent 24 months after a FIT+ result without registered correct follow-up—on DC completion and identified factors associated with correct follow-up. Methods: We included all individuals in the Flemish CRC screening program who had a FIT+ result between 2017 and 2019 and later received a failsafe letter due to lacking correct follow-up within 24 months. Correct follow-up was defined as a complete colonoscopy, virtual colonoscopy, or cancer diagnosis. We calculated the proportion of individuals completing correct follow-up within 24 months of the letter. Multivariable logistic regression examined associations between odds of correct follow-up and individual and area-level characteristics. Results: Of the 7175 individuals who received a failsafe letter, 16.1% completed correct follow-up within 24 months. Individuals aged 70–74 had significantly lower odds of correct follow-up than those aged 60–64 (odd ratio (OR) = 0.59; 95% confidence interval (CI): 0.48–0.72). Living in areas with a higher proportion of young adults in higher education was associated with higher odds of correct follow-up (OR = 1.041; 95% CI: 1.002–1.080). Conclusions: The failsafe letter modestly improved follow-up among a hard-to-reach group. Older age and lower area-level educational attainment were linked to reduced odds of correct follow-up. Targeted efforts are needed to improve DC completion in these subgroups.

1. Introduction

In Flanders, the population-based CRC screening program (CRC-SP), coordinated by the Centre for Cancer Detection (CCD), was launched in 2013. The program uses a centralized invitation process to offer a free fecal immunochemical test (FIT) by mail to people aged 50–74 years [1]. From 2013 until 2020, the FIT OC Sensor (Eiken, Chemical Co., Ltd., Tokyo, Japan) was used; since 2021, the program has used the FIT FOB Gold (Sentinel, Milano, Italy). Participation in the program is free of charge for the target population, and individuals are re-invited every 24 months following their last screening or last invitation for those who did not participate.
Both the participants and their general practitioner (GP)—if the GP was filled in the participation form and/or identified via a global medical dossier—receive the result of the FIT directly from the CCD. GPs are not required to contact their patients about their results. Among invitations sent in 2023, the program had a participation rate of 51.9%, with a FIT positivity rate of 6.2%, corresponding to 26,590 participants (and their GP) who received advice to undergo a diagnostic colonoscopy (DC) [2]. DCs—performed following a positive FIT result—are largely covered by the Belgian healthcare system, with participants bearing approximately 13% (mean average of euro (EUR) 85) [3].
DC compliance after a positive FIT is crucial to achieve an overall reduction in CRC incidence and mortality. Evidence from an Italian study indicates that the cumulative CRC mortality was 6.8 per 1000 among individuals who complied with colonoscopy recommendations after a positive FIT, compared with 16.0 per 1000 among non-compliers, corresponding to a more than twofold increase in risk (adjusted hazard ratio (HR) 2.03; 95% CI, 1.68–2.44) [4]. In Flanders, 15.8% (3690) of FIT-positive individuals in 2022 (23,404) did not undergo a DC (2023 data incomplete). Of these, 10.4% (2444) had no follow-up at all, and 5.4% had incorrect follow-up (1274) (e.g., a second stool test or an incomplete colonoscopy) [2,4].
Although the DC completion rate of 84.2% in Flanders aligns with international averages of approximately 80% [5,6] and nearly achieves the EU Guidelines’ acceptable level of 85%, it still falls short of the European (EU) Guidelines’ desirable level of >90% [7]. To address this, a failsafe mechanism was introduced in Flanders in March 2019. This mechanism involves sending a failsafe reminder letter—a postal recommendation—to individuals who have not completed a DC (or virtual colonoscopy) within 24 months after a positive FIT result (see Supplementary Materials S1-File S1 for the English translation of the letter). If the participant’s GP is known in the database, the letter is also sent electronically to the GP. The letter provides advice to undergo a DC and emphasizes the importance of having a colonoscopy rather than repeating a stool test after a positive FIT result. No new FIT is included. The term “failsafe” originates from the Dutch “faalveiligheid,” referring to a system designed to prevent failure; in this context, the letter acts as a safeguard to reduce missed follow-up. Due to administrative delays in registering colonoscopies—caused by the absence of a central colonoscopy register it is not possible to send the reminder letter immediately after a positive FIT result. Therefore, the failsafe letter is sent 24 months after the FIT+ result and replaces a new FIT invitation.
Previous studies in Flanders have shown that DC compliance after a positive FIT are associated with socio-demographic factors [1]. Older participants, lower socio-economic groups and non-Belgian nationalities are less likely to undergo a DC after a positive FIT [1]. Other Flemish research on FIT-positive individuals who did not undergo a DC revealed barriers to DC such as belief that the FIT result was a false positive one, lack of symptoms, competing medical priorities, fear of the colonoscopy procedure, and GP’s advice not to plan a DC [8]. To date, the impact of the failsafe reminder letter—sent 24 months after a positive FIT—on correct follow-up after a positive FIT has not been investigated. Therefore, the aim of this study was to evaluate the impact of this failsafe letter and to examine the associations between correct follow-up and individual-level as well as aggregated geographical characteristics among those who received a failsafe letter.

2. Results

2.1. Descriptive Analysis

Table 1 presents the characteristics of the study population. Among the 7161 individuals who received a failsafe letter, the largest age group was 60–64 years (26.3%), followed by 70–74 years (20.8%) and 55–59 years (20.1%). The youngest age group (50–54) was less represented, reflecting the gradual extension of the screening age range between 2017 and 2020. The majority of the study population was male (59.2%), and in 94.4% of the cases, the failsafe letter was also sent to the individual’s GP.
Regarding statistical sector-level characteristics, the median percentage of residents with Belgian nationality was 91.4%, and the median household size was 2.43 persons. The median percentage of young adults (aged 18–24) enrolled in higher education was 3.70%. The median average income was EUR 23,000.
Overall, 16.1% of individuals underwent a correct follow-up within 24 months after receiving the failsafe letter.

2.2. Univariable and Multivariable Analyses

Table 2 presents the p-values from likelihood ratio tests evaluating the association between each of the pre-defined determinants and the study outcome (i.e., whether a study subject had a correct follow-up within 24 months after receiving the failsafe letter).
In the univariable analyses, age group (p < 0.0001), percentage of Belgian nationality (p = 0.0102), average household size (p = 0.1429), percentage of residents in higher education (p = 0.0922), and average income (p = 0.1088) were associated with the study outcome (i.e., whether a study subject had a correct follow-up within 24 months after receiving the failsafe letter) at the threshold of p ≤ 0.2. In contrast, gender (p = 0.5122) and whether the failsafe letter was also sent to the GP (p = 0.2286) showed no significant association. Accordingly, the variables with p ≤ 0.2 in the univariable analyses were included in the final multivariable logistic regression model. Multicollinearity in the final multivariable model was low (generalized variance inflation factors (GVIF): 1.00–1.13). Table 2 summarizes the results of the final multivariable logistic regression model.
Compared with the age group 60–64 years (with largest count, used as the reference group), the age groups 50–54, 55–59 and 65–69 years showed no significant difference in the odds of having a correct follow-up after failsafe letter. However, the oldest age group 70–74 years had significantly lower odds of having a correct follow-up (OR = 0.59, 95%CI: 0.48–0.72). Among the statistical sector-level variables, a higher percentage of young adults (aged 18–24) enrolled in higher education (used as a proxy for education level) was significantly associated with increased odds of correct follow-up (OR = 1.041, 95%CI: 1.002–1.080). While both the percentage of individuals with Belgian nationality and average income were also statistically significantly associated with correct follow-up, their effect sizes were small (OR = 1.011, 95%CI: 1.004–1.0194 and OR = 0.976, 95%CI: 0.960–0.993, respectively), suggesting limited practical relevance.

3. Discussion

Our study found that 16.1% of individuals who received a failsafe letter underwent a correct follow-up within 24 months of receiving the letter. Several factors were associated with the odds of undergoing a correct follow-up. Individuals aged 70–74 had significantly lower odds of having a correct follow-up after the failsafe letter compared to those aged 60–64, while living in areas with a higher percentage of highly educated residents was associated with higher odds of correct follow-up.
The overall DC completion rate in the Flemish CRC-SP remains suboptimal, and DC non-compliance after a FIT+ result significantly reduces the benefits of population-based CRC screening. FIT+ participants are already at elevated risk for colorectal polyps and CRC. The absence of (timely) DC after a FIT+ result is associated with an increased risk of missed or late-stage CRC, leading to poorer outcomes and higher mortality [4,9].
Previous studies have identified barriers to DC completion at multiple levels, including patient, provider, health system and community factors [10,11]. Multilevel interventions are therefore needed to improve DC completion [6,11,12,13,14,15]. In Flanders, the failsafe system (reminder letters sent 24 months after a FIT+ result without a registered correct follow-up) was introduced in March 2019. These letters were sent to both the participant and GP if no correct follow-up was registered 24 months after a FIT+ result. Our study shows that this failsafe letter led to a correct follow-up in 16.1% of letter recipients. Although modest, this indicates a meaningful impact of the failsafe intervention on improving the correct follow-up rate among a hard-to-reach subgroup—individuals who did not complete a diagnostic colonoscopy (DC) despite receiving a positive FIT result.
Our findings suggest that the most important determinant of follow-up after the failsafe letter was age, with older individuals (70–74 years) significantly less likely to undergoa correct follow-up after receiving the failsafe letter. This may reflect concerns about comorbidities, limited life expectancy, or perceived risks of colonoscopy at older ages—both from the patient and provider perspectives [16]. In such cases, GPs may be reluctant to refer, and patients may prioritize other health issues or avoid invasive procedures. However, older FIT+ participants should benefit from possible needed treatment (after a DC) as well. A retrospective French study (including 57 patients of 70 and older) indicated that age did not impact survival outcomes after treatment for CRC [17]. Although a 100% DC completion rate may not be realistic for this age group, shared decision-making, guided by the GP’s knowledge of the patient’s overall health status, cognitive capacity, and personal preferences, remains essential.
Living in areas with a higher percentage of highly educated residents was associated with increased odds of undergoing a correct follow-up after receiving the failsafe letter. Higher education levels may indicate greater health literacy, better access to health information, and stronger engagement with preventive care [18,19,20]. Conversely, the importance of undergoing a DC after a FIT+ result may be less well known among lower-educated individuals, highlighting the need for tailored communication strategies to improve follow-up in this population.
Addressing barriers –such as costs, inconvenience, lack of symptoms, and fear of colonoscopy—is important. Provider recommendations, public health education and social support from family and peers have been shown to improve DC compliance [21]. Further interventions are needed to raise DC completion following a FIT+ result [22,23].
Several strategies have recently been implemented in Flanders to improve DC completion after a FIT+ result. Research has highlighted the importance of GP advice and social support from close contacts in motivating patients to undergo a DC [8,24]. Since 2019, a yearly leaflet has been distributed to GPs via social media and GP associations to raise awareness about the importance of a timely DC after a FIT+ result (and to discourage the inappropriate practice of performing a second stool test). In October 2024, this failsafe system was enhanced to send repeated failsafe letters every 24 months until a correct follow-up is registered. Furthermore, since 2022, a yearly individualized feedback report has been sent to ~6.000 in Flanders. This report includes the GP’s DC compliance rate among FIT+ patients, compared with regional and Flemish average, as well as a list of patients with no or incorrect follow-up after the FIT+ result. GPs or other health professionals can use this yearly report to further increase DC compliance among their patients.
Qualitative research into barriers to DC (e.g., lack of symptoms, misperception of false positives, fear, embarrassment, and costs of colonoscopy) also informed communication strategies. Modifications to the positive result letter included an infographic illustrating possible colonoscopy outcomes [8,24]. A testimonial video from a DC complier was developed, along with updated website content covering patient experiences, possible DC complications, and costs. This content is also shared through social media. In July 2025, a trial was launched in which a newly developed educational leaflet about the DC after a FIT+ result is added to the positive result letter in the intervention group, compared to a control group receiving the standard positive result letter only.
Sending a failsafe letter shortly after a FIT+ result is currently not feasible because of administrative delays in colonoscopy registration (caused by the absence of a central colonoscopy register). If such a letter were sent too soon (instead of 24 months later), many individuals who had already undergone a DC after a FIT+ result would still receive it, as the information would not yet be available to the CRC-SP, leading to redundant reminders. However, there has been evidence to suggest that automated SMS reminders sent immediately after the FIT+ result letter can be an effective way to increase DC compliance [11]. Similarly, mailed reminders have been shown to be as effective as telephone reminders, increasing DC completion by approximately 30% in an Italian study [25]. In response, a pilot study to test the effect of a short-term failsafe letter among DC non-compliers is planned to be implemented in the Flemish CRC-SP in 2026.
Finally, completing a DC after a FIT+ result is essential to finalize the CRC screening process. Since this DC is an integral part of the screening process, the DC should be fully covered by insurance, with no out-of-pocket cost for participants. Eliminating financial barriers may improve both clinical and economic outcomes [26]. Policy makers should ensure full coverage of DC to enhance completion rates and maximize the effectiveness of the CRC-SP in Flanders.

4. Materials and Methods

4.1. Study Population

Figure 1 shows the flow of participants through the study, detailing the steps and exclusions that led to the final study population. We started from a population of 1,074,002 individuals who participated in CRC screening in Flanders by submitting a FIT sample between 2017 and 2019 and who survived at least 24 months after FIT participation. Among these, 59,092 (5.5%) had a positive FIT result. Of the FIT-positive individuals, 50,577 underwent a correct follow-up within 24 months, while 8515 did not.
The study population included all screening episodes with a FIT+ result during 2017–2019, in which individuals did not have a correct follow-up within 24 months after the FIT+ result and thus received a failsafe letter. These individuals were followed up for 24 months after receiving the failsafe letter to assess whether a correct follow-up occurred within that period. Those who died within 24 months after receiving the failsafe letter (369) were excluded leaving 7474 eligible participants. Finally, 313 records were excluded due to missingness in at least one sector-level variable (see Section 4.4.1), resulting in 7161 screening episodes included in the final analysis.
A correct follow-up was defined as having a complete colonoscopy, a virtual colonoscopy (in cases where a complete colonoscopy was not possible) or a CRC diagnosis within the recommended period. An incorrect follow-up included no follow-up, a second stool test, an incomplete colonoscopy or any other follow-up procedures not considered correct follow-up after a FIT+ result.

4.2. Study Outcome

For each individual in the study, the primary outcome was whether a correct follow-up was performed within 24 months after receiving the failsafe letter from the Flemish CRC-SP. The outcome was recorded as a binary variable (no/yes).

4.3. Study Determinants

We assessed the associations between several characteristics of the study population and the study outcome (i.e., whether a correct follow-up was performed within 24 months after receiving a failsafe letter). These determinants include individual-level variables extracted from the screening database:
  • Age group (50–54; 55–59; 60–64; 65–69 & 70–74 years)
  • Gender (male/female)
  • Whether the failsafe letter was also sent to the person’s GP (no/yes)
Additional area-level variables were obtained at the level of statistical sector, the smallest administrative unit in Flanders at which population data are systematically collected. This level is comparable to the concept of a “neighbourhood” in the literature [27]. These sector-level variables, obtained from the Flemish provincial authorities’ database, served as proxies for individual-level demographic and socioeconomic status.
  • Belgian current nationality: percentage of residents with a Belgian current nationality (2024, continuous).
  • Household size: average number of individuals per household (2024, continuous).
  • Education level: percentage of residents aged 18–24 studying at a college/university (higher education), used as a proxy for education level (2023–2024, continuous).
  • Average income: total net taxable income divided by the number of residents as of 1 January of the tax year (2022, continuous).

4.4. Statistical Analysis

4.4.1. Missing Data

Data were complete for all the individual-level variables. Due to privacy reasons, figures were not displayed for cells with <5 events for the sector-level variables obtained from the database of the Flemish provincial authorities. Out of 7474 records that met our inclusion criteria, 313 records (4.2%) had missing data in at least one sector-level variable. As the amount of missing data was minimal and solely due to privacy concerns, complete case analysis was applied.

4.4.2. Sample Size

In total, our final analysis included 7161 screening episodes (i.e., individuals who received a failsafe letter), among which a correct follow-up was recorded in 1151 episodes. For logistic regression, at least 10 outcome events per predictor variable are required to ensure model stability and sufficient statistical power [28]. With 1151 outcome events and four determinants included in the final multivariable logistic regression model, our sample size was sufficient to meet this criterion.

4.4.3. Main Analyses

Descriptive analysis was conducted where the statistical sector-level variables were described with medians and interquartile ranges, while the individual-level variables were categorized and reported as proportions.
In the univariable analyses, we examined the association between each determinant and the study outcome (whether a correct follow-up was performed within 24 months after receiving the failsafe letter) using simple logistic regression. A likelihood ratio test was performed to compare each logistic regression model containing a single determinant with a null model containing only the intercept. Determinants with a p-value ≤ 0.2 in the likelihood ratio test were considered to significantly improve model fit and were retained for inclusion in the final multivariable logistic regression model. Multicollinearity in the multivariable model was assessed using variance inflation factors (VIFs). A more stringent p-value threshold of 0.05 was used for interpreting the results of the final multivariable model.
All analyses were conducted using RStudio (version 2025.05.0; RStudio, PBC, Boston, MA, USA).

5. Conclusions

This study shows that the failsafe letter implemented in the Flemish CRC-SP resulted in a correct follow-up in 16.1% of individuals who had not completed a DC after a FIT+ result. Although the overall impact was modest, the intervention successfully engaged a hard-to-reach subgroup and contributed to improved correct follow-up rates. Older people (70–74 years) were less likely to undergo a correct follow-up after the failsafe letter, while living in areas with a higher percentage of highly educated residents was associated with higher probability of correct follow-up. These insights emphasize the need for targeted communication strategies, system-level support, and continuous evaluation of policy interventions to address existing gaps in follow-up care. Further efforts are required to enhance DC completion among subgroups with lower correct follow-up rates after a FIT+ result.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/gidisord7040061/s1, File S1: English translation of the failsafe reminder letter used in the Flemish Colorectal Cancer Screening Program.

Author Contributions

Conceptualization, S.H.; writing—original draft preparation, S.H.; T.N.T. writing—review and editing, S.H.; T.N.T.; statistical analysis; visualization, T.N.T.; supervision, S.H. All authors have read and agreed to the published version of the manuscript.

Funding

The Flemish CRC screening programme is funded exclusively by the Agency for Care and Health, part of the Flemish Ministry of Welfare, Public Health and Family (https://www.vlaanderen.be/en, accessed on 24 September 2025. The Flemish Ministry was not involved in any phase of this study (design, data collection, analysis, interpretation, writing the manuscript).

Institutional Review Board Statement

The secondary use and linkage of the databases involved were approved on 17 September 2013 (updated on 20 March 2018), with reference number 13/091, and on 6 July 2021, with reference number 21/118, by the Information Security Committee (formerly the Committee for the Protection of Privacy). Approval of an ethical committee was not necessary given the fact that this retrospective study does not fall under the Belgian legislation for ethical committee approval (Law of 7 May 2004 regarding experiments on human persons (art. 3, Section 2)). Only pseudonymised data were used for this study, and results are reported in an aggregated way. The study protocol conforms to the principles of the 1964 Helsinki Declaration and its later amendments and to the applicable national guidelines.

Informed Consent Statement

Informed consent was obtained from all subjects involved in the study.

Data Availability Statement

Individual-level screening-related data (correct follow-up, age group, gender, whether the failsafe letter was also sent to the person’s GP) are available on request from the corresponding author upon reasonable request, due to privacy restrictions. Additional area-level data (Belgian current nationality, household size, education level, average income) are openly available through the Flemish provincial authorities’ database at https://provincies.incijfers.be/databank accessed on 22 September 2025.

Acknowledgments

We acknowledge the collaborators of the Belgian Cancer Registry (BCR). The CRC-SP in Flanders is organized at the regional level in Belgium, by the CCD. The CCD provides the BCR with data on invitations and participations, enabling the BCR to supply the CCD with necessary data on follow-up after a positive FIT in the CRC-SP, within existing data flows and legal frameworks. The Flemish CRC-SP can only develop failsafe mechanisms based on this follow-up data. We acknowledge the Flemish Colorectal Cancer Screening Task Force, for functioning as a sounding board.

Conflicts of Interest

The authors declare no conflicts of interest.

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Gastrointestdisord 07 00061 g001
Figure 1. Study population.
Figure 1. Study population.
Gastrointestdisord 07 00061 g001
Table 1. Characteristics of the study population.
Table 1. Characteristics of the study population.
CharacteristicsNumber (%) or
Median (IQR) 1
N = 7161
Individual-level variables
Age group
  50–54934 (13.0%) 2
  55–591439 (20.1%)
  60–641886 (26.3%)
  65–691409 (19.7%)
  70–741493 (20.8%)
Gender
  Male4237 (59.2%)
  Female2924 (40.8%)
Whether the failsafe letter was also sent to the person’s GP
  Yes6760 (94.4%)
  No 3401 (5.6%)
Statistical sector-level variables
Percentage of Belgian current nationality91.4 (83.7–95.4)
Average household size2.43 (2.16–2.50)
Percentage of having higher education3.70 (2.90–4.60)
Average income (per 1000 EUR)23.0 (21.0–25.0)
Outcome
whether a correct follow-up was performed after failsafe letter
  Yes1151 (16.1%)
  No6010 (83.9%)
1 Number (%) for individual-level variables and median (IQR) used for statistical sector-level variables. IQR, interquartile range; 2 The Flemish CRC-SP started in 2013 and the target ages were extended gradually from 56 to 74 in 2013, to 55 in 2017, 53–54 in 2018, 51–52 in 2019 and to 50 in 2020. The age group of 50–54 is therefore less represented in this study where only FIT+ of 2014–2019 are included; 3 The failsafe letter was not sent to the GP when no GP was provided or known at the time of participation.
Table 2. Determinants of having a correct follow-up performed within 24 months after receiving a failsafe letter.
Table 2. Determinants of having a correct follow-up performed within 24 months after receiving a failsafe letter.
CharacteristicsHaving a Correct Follow-Up After Failsafe Letter
Number (%) or Median (IQR) 1		aOR (95% CI)p-Value
No
(N = 6010)		Yes
(N = 1151)
Age group
60–641563 (26.0%)323 (28.1%)RefRef
50–54779 (13.0%)155 (13.5%)0.95 (0.77–1.17)0.6272
55–591160 (19.3%)279 (24.2%)1.16 (0.97–1.38)0.1082
65–691175 (19.6%)234 (20.3%)0.96 (0.80–1.15)0.6569
70–741333 (22.2%)160 (13.9%)0.58 (0.48–0.72)<0.0001 *
Percentage of Belgian current nationality91.3 (83.6–95.3)91.9 (84.4–95.6)1.011 (1.004–1.0194)0.0018 *
Average household size2.34 (2.16–2.50)2.35 (2.19–2.51)1.07 (0.85–1.34)0.5748
Percentage of having higher education3.60 (2.90–4.60)3.80 (3.00–4.60)1.041 (1.002–1.080)0.0385 *
Average income (per 1000 EUR)23.0 (21.0–26.0)23.0 (21.0–25.0)0.976 (0.960–0.993)0.0045 *
1 Number (%) for individual-level variables and median (IQR) used for statistical sector-level variables. IQR, interquartile range; * Statistically significant.
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MDPI and ACS Style

Hoeck, S.; Tran, T.N. Impact of a Failsafe Reminder Letter and Associated Factors on Correct Follow-Up After a Positive FIT in the Flemish Colorectal Cancer Screening Program. Gastrointest. Disord. 2025, 7, 61. https://doi.org/10.3390/gidisord7040061

AMA Style

Hoeck S, Tran TN. Impact of a Failsafe Reminder Letter and Associated Factors on Correct Follow-Up After a Positive FIT in the Flemish Colorectal Cancer Screening Program. Gastrointestinal Disorders. 2025; 7(4):61. https://doi.org/10.3390/gidisord7040061

Chicago/Turabian Style

Hoeck, Sarah, and Thuy Ngan Tran. 2025. "Impact of a Failsafe Reminder Letter and Associated Factors on Correct Follow-Up After a Positive FIT in the Flemish Colorectal Cancer Screening Program" Gastrointestinal Disorders 7, no. 4: 61. https://doi.org/10.3390/gidisord7040061

APA Style

Hoeck, S., & Tran, T. N. (2025). Impact of a Failsafe Reminder Letter and Associated Factors on Correct Follow-Up After a Positive FIT in the Flemish Colorectal Cancer Screening Program. Gastrointestinal Disorders, 7(4), 61. https://doi.org/10.3390/gidisord7040061

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