Relationship between health-related determinants and adherence to breast and colorectal cancer screening: a population-based study in Flanders, Belgium.

BACKGROUND: Despite the recognized benefits of structured cancer screening, tests outside organized screening programs are common. Comprehensive reports on outside program screening in Europe are lacking, but the Flemish breast cancer (BC) and colorectal cancer (CRC) screening programs monitor data on non-organized tests prescribed by GPs and specialists. METHODS: Using data at aggregated level, logistic regression was used to examine the relationship between health care utilization and screening coverage in 308 Flemish municipalities during 2015-18. RESULTS: With regards to BC, municipalities with higher rates of gynecologists' visits had lower odds of coverage inside (-8%) and higher odds of coverage outside (+17%) the program. By contrast, municipalities with higher rates of GP visits, had higher odds of coverage inside (+6%) and lower odds of coverage outside (-7%) the program. As for CRC, municipalities with higher rates of visits gastroenterologists' visits had lower odds of coverage inside (-3%). Instead, municipalities with higher rates of GP visits, had higher odds of coverage both inside (+2%) and outside (+5%) the program. Municipalities with higher percentages of people with chronic conditions had higher odds of coverage within both the BC and CRC programs (+5% and +3%), and lower odds of outside screening (-7% and -6%). Municipalities with higher percentages of people 65+ with dementia and with mood disorders had, respectively, higher odds (+13% and +5%) and lower odds (-3% and -4%) of coverage inside both the BC and CRC programs. CONCLUSION: Our findings underscore the impact of healthcare utilization on cancer screening coverage at the municipal level in Flanders.

Optimizing the colorectal cancer screening programme using faecal immunochemical test (FIT) in Flanders, Belgium from the "interval cancer" perspective.

BACKGROUND: Interval cancer (IC) is a critical issue in colorectal cancer (CRC) screening. We identified factors associated with ICs after faecal immunochemical test (FIT) screening and explored the impact of lowering FIT cut-off or shortening screening interval on FIT-ICs in Flanders. METHODS: FIT participants diagnosed with a CRC during 2013-2018 were included. Factors associated with FIT-ICs were identified using logistic regression. Distributions of FIT results among FIT-ICs were examined. RESULTS: In total, 10,122 screen-detected CRCs and 1534 FIT-ICs were included (FIT-IC proportion of 13%). FIT-ICs occurred more frequently in women (OR 1.58 [95% CI 1.41-1.76]) and ages 70-74 (OR 1.35 [1.14-1.59]). FIT-ICs were more often right-sided (OR 3.53 [2.98-4.20]), advanced stage (stage IV: OR 7.15 [5.76-8.88]), and high grade (poorly/undifferentiated: OR 2.57 [2.08-3.18]). The majority (83-92%) of FIT-ICs would still be missed if FIT cut-off was lowered from 15 to 10 µg Hb/g or screening interval was shortened from 2 to 1 year. CONCLUSIONS: FIT-ICs were more common in women, older age, right-sided location, advanced stage and high grade. In Flanders, lowering FIT cut-off (to 10 µg Hb/g) or shortening screening interval (to 1 year) would have a minimal impact on FIT-ICs.

Flemish population-based cancer screening programs: impact of COVID-19 related shutdown on short-term key performance indicators.

BACKGROUND: Many breast, colorectal, and cervical cancer screening programs were disrupted due to the COVID-19 pandemic. This study aimed to estimate the short-term impact of the temporary shutdown (from March until May- June) of the cancer screening programs invitations in Flanders (Belgium) by looking at invitation coverage, percentage of people screened after invitation and the screening interval. METHODS: Yearly invitation coverage was calculated as the number of people who received an invitation, as a proportion of the people who should have received an invitation that year. Weekly response to the invitation was calculated as the number of people who were screened within 40 days of their date of invitation, as a percentage of the people who received an invitation that week (as a proxy for willingness to screen). Weekly screening interval was calculated as the mean number of months between the current screening and the previous screening of all the people who screened that week. The two last indicators were calculated for each week in 2019 and 2020, after which the difference between that week's value in 2020 and 2019 with 95% confidence intervals. Results of these two indicators were also analysed after stratification for gender, age and participation history. RESULTS: Invitation coverage was not impacted in the colorectal and cervical cancer screening program. In the breast cancer screening program invitation coverage went down from 97.5% (2019) to 88.7% (2020), and the backlog of invitations was largely resolved in the first six months of 2021. The willingness to screen was minimally influenced by COVID-19. The breast cancer screening program had a temporary increase in screening interval in the first months following the restart after COVID-19 related shutdown, when it was on average 2.1 months longer than in 2019. CONCLUSIONS: Willingness to screen was minimally influenced by COVID-19, but there may be an influence on screening coverage because of lower invitation coverage, mainly for the for breast Cancer Screening Program. The increases in screening intervals for the three Cancer Screening Program seem reasonable and would probably not significantly increase the risk of delayed screening cancer diagnoses. When restarting a Cancer Screening Program after a COVID-19 related shutdown, monitoring is crucial.

Towards risk-stratified colorectal cancer screening. Adding risk factors to the fecal immunochemical test: Evidence, evolution and expectations.

With increasing incidence and mortality, colorectal cancer (CRC) is a growing health problem worldwide. An effective way to address CRC is by screening for fecal (occult) blood by the fecal immunochemical test (FIT). However, there is room for improvement since precursor lesions and CRC bleed intermittent and can therefore be missed by the FIT (false negatives) or, the detected blood did not result from precursor lesions or CRC (false positives). This review provides the latest evidence on risk prediction models using FIT combined with additional risk factors before colonoscopy, which risk factors to include and if these models will better discriminate between normal findings and CRC compared to the FIT-only. Many prediction models are known for CRC, but compared to the FIT, these are less effective in detecting CRC. The literature search resulted in 645 titles where 11 papers matched the inclusion criteria and were analyzed. Comparing the FIT-only with the risk prediction models for detecting CRC resulted in a significantly increased discrimination for the models. In addition, 2 different risk-stratification categories before colonoscopy were distinguished, namely the 1-model approach which combined risk factors with FIT results in a prediction model while the 2 step approach used risk factors apart from the FIT. Finally, combining FIT with CRC risk factors by means of a model before colonoscopy seems effective regarding discriminative power, however, more research is needed for validation combined with transparent and standardized reporting to improve quality assessment, for which suggestions are reported in this study.

Unhealthy drinking in the Belgian elderly population: prevalence and associated characteristics.

BACKGROUND: Knowledge about alcohol consumption patterns and alcohol problems among the Belgian elderly population is scarce. The aims of this study were to explore alcohol consumption patterns and alcohol problems among the Belgian elderly population aged ≥ 65 years living at home, and to determine their association with socio-demographic characteristics, health status and socio-economic status. METHODS: In this cross-sectional study based on a representative sample of 4825 non-institutionalized Belgian elderly people (≥ 65 years) in the Belgian Health Interview Surveys 2001 and 2004, alcohol consumption patterns and alcohol problems were estimated according to age, gender, survey year, living situation, frequency of social contacts, smoking status, and socio-economic status. RESULTS: In all, 50.4% of the sample were non- or occasional drinkers, 29.1% were moderate drinkers, 10.4% at-risk drinkers, 4.6% heavy drinkers and 5.5% problematic drinkers. In total, 20.5% of the Belgian elderly population drank in excess of the National Institute on Alcohol Abuse and Alcoholism guidelines, and 4.7% had an alcohol problem according to the CAGE. In addition, 81.3% of the elderly people who consume alcohol used prescribed medications in the past 2 weeks. After adjustment for risk factors we found that, compared with moderate drinking, unhealthy drinking was significantly associated with age, gender, frequency of social contacts, health status and socio-economic status. CONCLUSIONS: Belgian health policy should be aware of the high level of at-risk drinkers in the elderly population and the underdetection and misdiagnosis of alcohol problems in this age group. An increased attention in public health initiatives among the Belgian elderly population is needed.

The Impact of a Six-Year Existing Screening Programme Using the Faecal Immunochemical Test in Flanders (Belgium) on Colorectal Cancer Incidence, Mortality and Survival: A Population-Based Study.

The faecal immunochemical test (FIT) has been increasingly used for organised colorectal cancer (CRC) screening. We assessed the impact of a six-year existing FIT screening programme in Flanders (Belgium) on CRC incidence, mortality and survival. The Flemish CRC screening programme started in 2013, targeting individuals aged 50-74 years. Joinpoint regression was used to investigate trends of age-standardised CRC incidence and mortality among individuals aged 50-79 years (2004-2019). Their 5-year relative survival was calculated using the Ederer II method. We found that FIT screening significantly reduced CRC incidence, especially that of advanced-stage CRCs (69.8/100,000 in 2012 vs. 51.1/100,000 in 2019), with a greater impact in men. Mortality started to decline in men two years after organised screening implementation (annual reduction of 9.3% after 2015 vs. 2.2% before 2015). The 5-year relative survival was significantly higher in screen-detected (93.8%) and lower in FIT non-participant CRCs (61.9%) vs. FIT interval cancers and CRCs in never-invited cases (67.6% and 66.7%, respectively). Organised FIT screening in Flanders clearly reduced CRC incidence (especially advanced-stage) and mortality (in men, but not yet in women). Survival is significantly better in screen-detected cases vs. CRCs in unscreened people. Our findings support the implementation of FIT organised screening and the continued effort to increase uptake.

Health-care and home-care utilization among frail elderly persons in Belgium.

BACKGROUND: The patterns of health- and home-care utilization among Belgian frail elderly persons living at home with varying socio-economic status are currently unknown. METHODS: In this cross-sectional study based on a representative sample of 4777 elderly participants (≥65 years) in the Belgian Health Interview Survey the prevalence of frailty, as determined by items referring to the Fried phenotype, was estimated according to age, gender, comorbidity, place of residence, survey year, living situation and socio-economic status. Differing health-care utilization [contacts with a general practitioner (GP), specialist and emergency department; and hospital admission) and home-care utilization (home nursing, home help and meals-on-wheels] patterns among the frail, prefrail and robust subpopulations were examined. RESULTS: Overall, 9.3% respondents (426) were classified as frail, 30.7% (1636) as prefrail and 60.0% (2715) as robust. Frailty was associated with age, gender, comorbidity, region, survey year and socio-economic status. The frail and prefrail groups were more likely than the robust to contact a GP, a specialist or an emergency department and were more likely to be admitted to hospital, independent of age, gender, comorbidity, survey year, living situation, region and socio-economic status. They were also more likely to appeal to home nursing, home help and meals-on-wheels than the robust participants. CONCLUSION: Even after adjustment for potential confounders, including age, gender and comorbidity, frailty among Belgian elderly persons is associated with their socio-economic status and is strongly associated with their health- and home-care utilization.

Barriers and facilitators to participate in the colorectal cancer screening programme in Flanders (Belgium): a focus group study.

OBJECTIVE: In Flanders (Belgium), a population-based colorectal cancer (CRC) screening programme offers a faecal immunochemical test (FIT) biennially to Flemish citizens aged 50-74 years. A FIT uptake of only 51,5% in 2018 is significantly lower among men, lower income groups and among people with other than the Belgian nationality.The objective of this study was to identify attitudes, barriers and facilitators to participate in the Flemish CRC screening programme. METHODS: Qualitative study using focus group discussions (FGDs) with non-participants in the Flemish CRC screening programme. Four FGDs were held with non-migrant Flemish population groups, and four were held with Turkish migrants (41 participants). RESULTS: Feeling healthy, fear of cancer and embarrassment to talk about CRC screening emerged as common barriers in all FGDs. Having other priorities (non-migrant group) and a lack of understanding mainly due to a language barrier (Turkish migrants) differed between the two groups. Providing face-to-face information, information in group and GP recommendation were perceived as important facilitators to CRC screening in both groups. More publicity and making CRC screening more of a routine (non-migrant group) and offering translated information (Turkish migrants) were the suggested facilitators that differed between the groups. CONCLUSIONS: Several common and some group-specific barriers and facilitators appeared to play a role in the decision to participate in the CRC screening programme. In order to improve informed decision making and participation in the CRC screening programme in Flanders, the options of more GP involvement, targeted information events, and adapted reminder letters are currently being explored.

Towards Novel Non-Invasive Colorectal Cancer Screening Methods: A Comprehensive Review.

Colorectal cancer (CRC) is one of the leading cancer-related causes of death in the world. Since the 70s, many countries have adopted different CRC screening programs, which has resulted in a decrease in mortality. However, current screening test options still present downsides. The commercialized stool-based tests present high false-positive rates and low sensitivity, which negatively affects the detection of early stage carcinogenesis. The gold standard colonoscopy has low uptake due to its invasiveness and the perception of discomfort and embarrassment that the procedure may bring. In this review, we collected and described the latest data about alternative CRC screening techniques that can overcome these disadvantages. Web of Science and PubMed were employed as search engines for studies reporting on CRC screening tests and future perspectives. The searches generated 555 articles, of which 93 titles were selected. Finally, a total of 50 studies, describing 14 different CRC alternative tests, were included. Among the investigated techniques, the main feature that could have an impact on CRC screening perception and uptake was the ease of sample collection. Urine, exhaled breath, and blood-based tests promise to achieve good diagnostic performance (sensitivity of 63-100%, 90-95%, and 47-97%, respectively) while minimizing stress and discomfort for the patient.

Population-Based Data Reveal Factors Associated with Organised and Non-Organised Colorectal Cancer Screening: An Important Step towards Improving Coverage.

We investigated factors associated with organised and non-organised colorectal cancer screening using faecal occult blood tests, based on data from 308 municipalities in Flanders (6.6 million residents, 57% of Belgium) during 2015-2017. Logistic regression with generalized estimating equations was used to assess the associations between municipal characteristics and organised and non-organised screening coverages. Factors associated negatively with both organised and non-organised screening: percentage of people aged 70-74 in the target population [OR (odds ratios) = 0.98, 95%CI (confidence interval): 0.97-0.99 and OR = 0.98, 95%CI: 0.96-0.999, respectively]; negatively with organised screening: average income [OR = 0.97, 95%CI: 0.96-0.98], percentage of people with a non-Belgian/Dutch nationality [OR = 0.962, 95%CI: 0.957-0.967]; positively with organised screening: percentages of men in the target population [OR = 1.13, 95%CI: 1.11-1.14], jobseekers [OR = 1.12, 95%CI: 1.09-1.15] and people with at least one general practitioner (GP) visit in the last year [OR = 1.04, 95%CI: 1.03-1.05]; positively with non-organised screening: number of patients per GP [OR = 1.021, 95%CI: 1.016-1.026], percentage of people with a global medical dossier handled by a preferred GP [OR = 1.025, 95%CI: 1.018-1.031]. This study helps to identify the hard-to-reach subpopulations in CRC screening, and highlights the important role of GPs in the process of promoting screening among non-participants and encouraging non-organised participants to switch to organised screening.

Uptake of cancer screening among adults with disabilities in Flanders (Belgium).

Objective: To explore the association between disability and participation in breast, cervical, and colorectal cancer screening in Flanders (Belgium). Methods: Data from the Centre for Cancer Detection were linked to data of the Flemish Agency for disabled persons by the Crossroads Bank for Social Security, using National Social Security Numbers. Results: The study population consisted of 92,334 invited individuals registered as disabled in 2013­2015. For breast cancer screening (including both opportunistic screening and participation in the screening program), 51.7% of disabled women had undergone mammography in the last two years, compared with the Flemish uptake of 61.8%. In cervical screening, 45% of the women with a disability had undergone a PAP smear in the last three years (overall Flemish uptake was 60.7%). For colorectal cancer screening, 40.7% of individuals with a disability had undergone a fecal immunochemical test in the last two years (overall Flemish uptake was 51.5%). Participation in breast and colorectal cancer screening among persons with a disability was 10% points less than the Flemish average during the same period. In the cervical cancer screening program, the difference between the participation of disabled women and the Flemish average was 10% points. Persons with any type of disability had a lower uptake of cancer screening than the Flemish average, except for individuals with a hearing impairment. Conclusions: Participation disparities in the Flemish cancer screening programs between persons with and without disabilities require specific efforts to increase cancer screening among people with a disability.

Occurrence and characteristics of faecal immunochemical screen-detected cancers vs non-screen-detected cancers: Results from a Flemish colorectal cancer screening programme.

BACKGROUND: Colorectal cancer (CRC) and its precursor lesions are detected at an early stage by CRC screening programmes, which reduce CRC-related mortality. An important quality indicator for CRC screening is the occurrence of interval CRC (IC) between screening rounds. Currently there is no guideline regarding acceptable levels of ICs in CRC screening programmes, and ICs reported in prior work vary considerably. METHODS: This study describes the occurrence of screen-detected (SD) CRC and non-screen-detected CRC within the population-based CRC screening programme of Flanders, stratified by multiple variables such as sex, age, tumour location and tumour stage between October 2013 and July 2017. In addition, faecal immunochemical test (FIT) IC proportions over the sum of SD-CRCs and FIT-ICs are calculated, together with FIT sensitivity and programme sensitivity to display the effectiveness of detecting CRC by the screening programme. RESULTS: Of 1,212,354 FIT participants, 4094 were diagnosed with SD-CRC, whereas 772 participants were diagnosed with CRC between FIT-screening rounds. Significant associations were shown between people not being SD for CRC and women, older individuals, right-sided tumour location and more advanced tumour stage. Furthermore, a clear distinction was shown between the right-sided and the left-sided colorectum concerning all above-mentioned variables and distributions of tumour stages. CONCLUSION: The Flemish FIT-interval CRC proportion of 15.9% was within the limits of previously published results. In addition, calculations show that the effectiveness of the screening programme is dependent on tumour location, suggesting that future research should report results stratified by location.

Participation in faecal immunochemical testing-based colorectal cancer screening programmes in the northwest of Europe.

OBJECTIVE: This study compared the participation in four faecal immunochemical testing-based screening programmes for colorectal cancer in Flanders, France, Basque country and the Netherlands, to identify factors to further optimize faecal immunochemical testing programmes. METHOD: Background information and data on performance indicators were collected and compared for the four programmes. RESULTS: Invitation method, reminders, funding, faecal immunochemical testing cut-off and follow-up after positive faecal immunochemical testing differed in the four programmes. In France, only an invitation letter is sent by mail, while the sample kit must be collected from the general practitioner. In the other programmes, an invitation letter including the sample kit is sent by mail. Participation rates vary substantially according to the method of invitation, with the highest participation rates in the Netherlands (73.0%) and Basque country (72.4%), followed by Flanders (54.5%) and France (28.6%). Basque country (92.8%) and France (88.4%), the two programmes with most active involvement of general practitioners in referral for colonoscopy, had the highest participation rates for colonoscopy. CONCLUSIONS: Large differences in screening participation observed between programmes according to the invitation method used suggest that changes to the design of the programme, such as including the sample kit with the invitation, or active involvement of GPs, might increase participation.

Should Flanders consider lowering its target age for colorectal cancer screening to 45-49?

INTRODUCTION: Colorectal cancer (CRC) screening generally starts screening by the age of 50 based on guidelines. Lately however, a U.S. guideline recommended to start CRC screening from age 45 and, very recently, two studies were published that addressed young-onset in Europe (in part) (Vuik et al., 2019; Araghi et al., 2019). MATERIALS AND METHODS: Flemish CRC incidence and mortality data contextualise trend results for age groups under 50 and what the implications could be for practice. RESULTS: CRC incidence rates showed considerable variability over a 12-year period without a clear increase in disease burden for the age group 45-49 in Flanders. In several age groups under 39 an increasing incidence trend was visible for both genders. Data was analysed in a period where no CRC screening was present in Flanders. DISCUSSION: Decreasing the target age for the Flemish CRC screening does not seem to be straightforward and primary prevention should be considered more prominently.

Risk stratification for colorectal neoplasia detection in the Flemish colorectal cancer screening programme.

BACKGROUND: The quantitative faecal immunochemical test (FIT) detects pre-cancerous lesions and colorectal cancer (CRC). Current CRC screening programmes are based upon a binary FIT result. This study evaluates the possibility of personalised risk prediction, based on FIT, age and gender to gain more insight into improving discrimination between normal outcomes, pre-cancerous lesions, carcinoma in situ and CRC working towards a more tailored screening approach. METHODS: In this retrospective study, from October 2013 until July 2016, data from 57,421 participants who underwent a colonoscopy after a positive FIT in the Flemish CRC screening programme were analysed using a multinomial multivariable logistic regression model. RESULTS: A significant difference in risk of detecting neoplasia was found between the established risk profiles based on the combination of the quantitative FIT, age and gender. The odds for detecting CRC in men aged 74, with a FIT result of ≥1000 ng/ml, was higher by a factor of 58.43 than that for women aged 56, with a FIT result of 75 ng/ml. CONCLUSION: A large difference in risk with regard to the detection of colorectal neoplasia was found, based on demographics of the population. For some participants, the chance of finding no anomalies was more than 60%. Including additional variables in a prediction model could further increase discrimination between outcomes and practicality.

Equity in GP and specialist contacts by older persons in Belgium.

OBJECTIVES: To explore the existence of socioeconomic differences in probability and intensity of general practitioner (GP) and specialist contacts among the Belgian elderly population, compared with the younger population. METHODS: A nationally representative cross-sectional study based on 4,825 older (≥65) and 14,738 younger participants (<65) in the Belgian Health Interview Surveys 2001 and 2004. Socioeconomic differences in contacts with a GP and specialist were examined using two-part hurdle models; use versus nonuse by logistic regression, and intensity of use by zero-truncated negative binomial regression. RESULTS: The intermediate income group was more likely to contact a GP and tenants reported more GP contacts. Lower educated older persons were less likely to contact a specialist and household income seemed to play a role in the intensity of specialist contacts. CONCLUSIONS: The probability and intensity of general practitioner and specialist contacts among the Belgian older population are mainly determined by sociodemographic and health status variables, but a certain degree of inequity remains. The socioeconomic gradient differs in probability and intensity of contacts, indicating the advantage of using a two-part model in investigating socioeconomic differences in healthcare utilisation.

Preventive care use among the Belgian elderly population: does socio-economic status matter?

OBJECTIVE: To analyze the association between influenza and pneumococcus vaccination and blood cholesterol and blood sugar measurement by Belgian elderly respondents (≥ 65 years) and socio-demographic characteristics, risk factors, health status and socio-economic status (SES). METHODS: A cross-sectional study based on 4,544 non-institutionalized elderly participants of the Belgian Health Interview Surveys 2004 and 2008. Multivariate logistic regression models were constructed to examine the independent effect of socio-demographic characteristics, risk factors, health status and SES on the four preventive services. RESULTS: After adjustment for age, sex, region, survey year, living situation, risk factors (body mass index, smoking status, physical activity) and health status (self-assessed health and longstanding illness) lower educated elderly were significantly less likely to report a blood cholesterol and blood sugar measurement. For instance, elderly participants with no degree or only primary education were less likely to have had a cholesterol and blood sugar measurement compared with those with higher education. Pneumococcus vaccination was not related to educational level, but lower income groups were more likely to have had a pneumococcus immunization. Influenza vaccination was not significantly related to SES. CONCLUSION: The results highlight the need to promote cholesterol and blood sugar measurement for lower SE groups, and pneumococcus immunization for the entire elderly population. Influenza immunization seems to be equally spread among different SE groups.

Experiences of parents of substance-abusing young people attending support groups.

BACKGROUND: Substance abuse puts a burden on the physical and mental health and well-being of individuals and their families, particularly parents. Parents of substance-abusing young people are in need of professional or informal support and information. Potential and easy accessible sources are support groups. We explored the experiences of parents of substance-abusing young people attending support groups regarding several topics related to the substance-abuse of their son or daughter, the impact on their lives and their views on social support. METHODS: In this small-scale qualitative study based on in-depth interviews, we interviewed parents of substance-abusing young people focusing on their experiences concerning having a substance-abusing relative and attending the support group. RESULTS: All parents displayed feelings of stress and strain. They appeared to be highly satisfied with their participation in a support group. The expert status and knowledge of the facilitator and the provision of accurate information in the support group was also much appreciated. They were however dissatisfied by the attitude and knowledge of their GP. CONCLUSIONS: Our findings suggest that parents benefit from joining support groups, particularly in terms of emotional and social support and the practical information they received.

Population-based screening for colorectal cancer using an immunochemical faecal occult blood test: a comparison of two invitation strategies.

BACKGROUND: To date, there is no screening programme for colorectal cancer (CRC) in Flanders, Belgium. However, The European Code Against Cancer (2003) recommends a population-based approach for CRC screening. This study aimed to obtain information about potential participation rates for a population-based screening programme for CRC in Flanders, and to compare two invitation strategies. METHODS: In 2009, a trial programme for CRC screening was set up in three Flemish areas for all average-risk people aged 50-74 years, using an immunochemical faecal occult blood test (iFOBT) with a cut-off value set at 75 ng/ml of haemoglobin. The faecal sampling set was sent at random by post (mail group) or provided by the general practitioner (GP group). RESULTS: In total, 19,542 people were invited to participate. Of these, 8229 provided a faecal sample, resulting in an overall participation rate of 42.1%. Participation by mail and through the GP was 52.3% (95% CI, 51.3-53.2) and 27.7% (95% CI, 26.7-28.6), respectively. The difference of 24.6% was statistically significant (95% CI, 23.3-25.9, p<0.001). Before the reminder letter was sent and the other invitation strategy was offered, the overall participation rate was 26.5% (n=5176); 36.4% (95% CI, 35.5-37.4) for the mail group and 16.6% (95% CI, 15.8-17.3) for the GP group. The odds of participating in CRC screening was almost three times higher for people invited by mail as opposed to people invited through a GP (OR=2.96, 95% CI, 2.78-3.14, p<0.001). Women were more likely to participate in CRC screening than men (OR=1.22, 95% CI, 1.15-1.30, p<0.001). In addition, we found that inhabitants from residential (OR=1.98, 95% CI, 1.85-2.11) and rural (OR=2.90, 95% CI, 2.66-3.16) areas were more likely to participate than those in urban areas. Of the 8229 people who submitted a faecal sample, 435 (5.3%) had a positive iFOBT, and of those, CRC was diagnosed in 18 (5.7%) individuals. Compliance for follow-up colonoscopy was 72.9%, and did not differ between the mail (72.4%, 95% CI, 67.5-77.3) and GP groups (74.3, 95% CI, 66.2-82.5). CONCLUSION: Inviting people for CRC screening by means of a direct-mail invitation, and including a faecal sampling set (iFOBT), results in much higher participation rates than inviting people through the GP.