Predictors of repeat participation in the NHS bowel cancer screening programme

Comparing a fecal immunochemical test and circulating tumor DNA blood test for colorectal cancer screening adherence

BACKGROUND AND AIM

Colorectal cancer (CRC) screening programs are most effective at reducing disease incidence and mortality through sustained screening participation. A novel blood test modality is being explored for CRC screening, but it is unclear whether it will provide sustained screening participation. This study aimed to investigate whether a circulating tumor DNA (ctDNA) blood test improved CRC screening re-participation when compared with a fecal immunochemical test (FIT) and to define the predictors of sustained CRC screening in an Australian population.

METHODS

South Australians who initially participated in CRC screening using a ctDNA blood test (n = 36) or FIT (n = 547) were offered the same CRC screening test approximately 2 years later through an extended phase of a randomized controlled trial. Surveys collected demographic, psychosocial, and clinical information. Predictors of CRC screening re-participation were explored using chi-square, Wilcoxon tests, and logistic regression.

RESULTS

Participants offered a second ctDNA blood test were equally likely to re-participate in CRC screening as those who completed a FIT in the first round and who were offered the same test (61% vs 66% re-participation respectively, P = 0.6). CRC fatalism, health activation, and self-efficacy were associated with repeated screening participation. Test awareness was predictive of repeated FIT-based CRC screening.

CONCLUSIONS

Targeted interventions to improve CRC screening awareness and increase patient health activation may improve CRC screening adherence. A ctDNA blood test may be a suitable CRC screening option to maintain CRC screening adherence in people who do not participate in screening with FIT.

Subsequent participation in organized FIT based screening following screen-derived colonoscopy - A Danish nationwide cohort study

Introduction

In the Danish National Colorectal Cancer (CRC) screening program, participants with screen-detected low-risk adenomas are invited to a new faecal immunochemical test (FIT) screening after two years. However, participation rate in next FIT screening is unknown. We aimed to investigate this subsequent participation rate within the Danish CRC screening program.

Methods

This nationwide register-based study included participants aged 50-72 years registered with FIT screening in the Danish CRC screening program between January 1, 2016, and June 30, 2017. Participants were included if their index FIT was negative or if it was positive and the subsequent colonoscopy detected low-risk adenomas. Invitees were categorized as subsequent participants if they returned a FIT within 135 days following the invitation to screening. We estimated the relative risk for participation depending on screening outcome, age, and sex.

Result

415,107 with a negative result and 5,550 with low-risk adenomas were included. 86.0% (85.9;86.1) of the invitees with a negative result participated in the subsequent screening, while 71.8% (70.6;73.0) of the invitees with low-risk adenomas participated subsequently. The risk of participation in the subsequent screening was significantly lower among all age groups of men and women with low-risk adenomas compared to similar groups with negative results.

Conclusion

Invitees with low-risk adenomas detected at their initial colonoscopy are less likely to participate in the subsequent screening than invitees with negative results. This association was found in all age groups and for both sexes. Further studies are necessary to assess whether non-attendance is more pronounced in specific subgroups.

Mediators of screening uptake in a colorectal cancer screening intervention among Hispanics

Background

Colorectal cancer (CRC) is the second leading cause of cancer deaths in the USA. Although a number of CRC screening tests have been established as being effective for CRC prevention and early detection, rates of CRC screening test completion in the US population remain suboptimal, especially among the uninsured, recent immigrants and Hispanics. In this study, we used a structural equation modelling approach to identify factors influencing screening test completion in a successful CRC screening program that was implemented in an uninsured Hispanic population. This information will enhance our understanding of influences on CRC screening among historically underscreened populations.

Methods

We used generalized structural equation models (SEM) utilizing participant reported information collected through a series of surveys. We identified direct and indirect pathways through which cofactors, CRC knowledge and individual Health Belief Model constructs (perceived benefits, barriers, susceptibility, fatalism and self-efficacy) and a latent psychosocial health construct mediated screening in an effective prospective randomized CRC screening intervention that was tailored for uninsured Hispanic Americans.

Results

Seven hundred twenty-three participants were eligible for inclusion; mean age was 56 years, 79.7% were female, and 98.9% were Hispanic. The total intervention effect was comparable in both models, with both having a direct and indirect effect on screening completion (n = 715, Model 1: RC = 2.46 [95% CI: 2.20, 2.71, p < 0.001]; n = 699, Model 2 RC =2.45, [95% CI: 2.18, 2.72, p < 0.001]. In Model 1, 32% of the overall effect was mediated by the latent psychosocial health construct (RC = 0.79, p < 0.001) that was in turn mainly influenced by self-efficacy, perceived benefits and fatalism. In Model 2, the most important individual mediators were self-efficacy (RC = 0.24, p = 0.013), and fatalism (RC = 0.07, p = 0.033).

Conclusion

This study contributes to our understanding of mediators of CRC screening and suggests that targeting self-efficacy, perceived benefits and fatalism could maximize the effectiveness of CRC screening interventions particularly in Hispanic populations.

The integrated screening action model (I-SAM): A theory-based approach to inform intervention development

Screening can reduce deaths if the people invited participate. However, good uptake is hard to achieve, and our current approaches are failing to engage the most vulnerable. A coherent model of screening behaviour to guide our understanding and intervention development is yet to be established. The present aim was to propose an Integrated Screening Action Model (I-SAM) to improve screening access. The I-SAM synthesises existing models of health behaviour and empirical evidence. The I-SAM was developed following: i) an appraisal of the predominant models used within the screening literature; ii) the integration of the latest knowledge on behaviour change; with iii) the empirical literature, to inform the development of a theory-based approach to intervention development. There are three key aspects to the I-SAM: i) a sequence of stages that people pass through in engaging in screening behaviour (based on the Precaution Adoption Process Model); ii) screening behaviour is shaped by the interaction between participant and environmental influences (drawing from the Access Framework); and iii) targets for intervention should focus on the sources of behaviour - 'capability', 'opportunity', and 'motivation' (based on the COM-B Model). The I-SAM proposes an integrated model to support our understanding of screening behaviour and to identify targets for intervention. It will be an iterative process to test and refine the I-SAM and establish its value in supporting effective interventions to improve screening for all.

Inequalities in participation in colorectal cancer screening programmes: a systematic review

BACKGROUND

Colorectal cancer (CRC) is a major public health problem due to its incidence and mortality. Screening programmes help decrease its impact on the population through early detection. However, the uneven distribution of social determinants of health can cause inequalities. The aim of this study is to identify the social inequalities in the participation in CRC screening programmes.

METHODS

A systematic review of the literature was carried out, searching in both health and social databases for papers published since 2000 in English, Spanish, Portuguese and French. The search strategies combined terms regarding screening, CRC, participation and social inequalities. Included papers were quantitative or qualitative primary studies analyzing gender and socioeconomic inequalities in the participation in CRC screening programmes implemented by public and private health-care providers and addressing 45- to 75-year-old population.

RESULTS

A total of 96 studies, described in 102 articles, were included. Most were quantitative observational studies and analyzed population-based screening programmes. They were carried out mainly in the UK (n=29) and the USA (n=18). Participation in screening programmes varied from 1.1% to 82.8% using several methods. A total of 87 studies assessed participation by sex and one focussed on men, but only two provided an analysis from a gender perspective. Although men are at a higher risk of developing CRC, they generally were less likely to participate in screening programmes. Screening attendance was higher among the least deprived areas.

CONCLUSIONS

Gender and socioeconomic inequalities in CRC screening participation should be addressed through the design of tailored interventions with a multidimensional focus.

Comparing the Cost-Effectiveness of Innovative Colorectal Cancer Screening Tests

Background

Colorectal cancer (CRC) screening with colonoscopy and the fecal immunochemical test (FIT) is underused. Innovative tests could increase screening acceptance. This study determined which of the available alternatives is most promising from a cost-effectiveness perspective.

Methods

The previously validated Microsimulation Screening Analysis-Colon model was used to evaluate the cost-effectiveness of screening with capsule endoscopy every 5 or 10 years, computed tomographic colonography every 5 years, the multi-target stool DNA test every 1 or 3 years, and the methylated SEPT9 DNA plasma assay (mSEPT9) every 1 or 2 years. We also compared these strategies with annual FIT screening and colonoscopy screening every 10 years. Quality-adjusted life-years gained (QALYG), number of colonoscopies, and incremental cost-effectiveness ratios were projected. We assumed a willingness-to-pay threshold of $100 000 per QALYG.

Results

Among the alternative tests, computed tomographic colonography every 5 years, annual mSEPT9, and annual multi-target stool DNA screening had incremental cost-effectiveness ratios of $1092, $63 253, and $214 974 per QALYG, respectively. Other screening strategies were more costly and less effective than (a combination of) these 3. Under the assumption of perfect adherence, annual mSEPT9 screening resulted in more QALYG, CRC cases averted, and CRC deaths averted than annual FIT screening but led to a high rate of colonoscopy referral (51% after 3 years, 69% after 5 years). The alternative tests were not cost-effective compared with FIT and colonoscopy.

Conclusions

This study suggests that for individuals not willing to participate in FIT or colonoscopy screening, mSEPT9 is the test of choice if the high colonoscopy referral rate is acceptable to them.

Measures of longitudinal adherence to fecal-based colorectal cancer screening: Literature review and recommended approaches

The success of fecal occult blood-based colorectal cancer screening programs is dependent on repeating screening at short intervals (ie, every 1-2 years). We conducted a literature review to assess measures that have been used to assess longitudinal adherence to fecal-based screening. Among 46 citations identified and included in this review, six broad classifications of longitudinal adherence were identified: (a) stratified single-round attendance, (b) all possible adherence permutations, (c) consistent/inconsistent/never attendance, (d) number of times attended, (e) program adherence and (f) proportion of time covered. Advantages and disadvantages of these measures are described, and recommendations on which measures to use based on data availability and scientific question are also given. Stratified single round attendance is particularly useful for describing the yield of screening, while programmatic adherence measures are best suited to evaluating screening efficacy. We recommend that screening programs collect detailed longitudinal, individual-level data, not only for the screening tests themselves but additionally for diagnostic follow-up and surveillance exams, to allow for maximum flexibility in reporting adherence patterns using the measure of choice.

A Systematic Review of Repeat Fecal Occult Blood Tests for Colorectal Cancer Screening

Screening with fecal occult blood tests (FOBT) reduces colorectal cancer mortality. Failure to complete repeat tests may compromise screening effectiveness. We conducted a systematic review of repeat FOBT across diverse health care settings. We searched MEDLINE, Embase, and the Cochrane Library for studies published from 1997 to 2017 and reported repeat FOBT over ≥2 screening rounds. Studies (n = 27 reported in 35 articles) measured repeat FOBT as (i) proportion of Round 1 participants completing repeat FOBT in Round 2; (ii) proportion completing two, consecutive FOBT; or (iii) proportion completing ≥3 rounds. Among those who completed FOBT in Round 1, 24.6% to 89.6% completed repeat FOBT in Round 2 [median: 82.0%; interquartile range (IQR): 73.7%-84.6%]. The proportion completing FOBT in two rounds ranged from 16.4% to 80.0% (median: 46.6%; IQR: 40.5%-50.0%), and in studies examining ≥3 rounds, repeat FOBT ranged from 0.8% to 64.1% (median: 39.2%; IQR: 19.7%-49.4%). Repeat FOBT appeared higher in mailed outreach (69.1%-89.6%) compared with opportunistic screening (24.6%-48.6%). Few studies examined correlates of repeat FOBT. In summary, we observed a wide prevalence of repeat FOBT, and prevalence generally declined in successive screening rounds. Interventions that increase and maintain participation in FOBT are needed to optimize effectiveness of this screening strategy.

Do socioeconomic factors play a role in nonadherence to follow-up colonoscopy after a positive faecal immunochemical test in the Flemish colorectal cancer screening programme?

OBJECTIVE

In Flanders (Belgium), a population-based colorectal cancer (CRC) screening programme was started in 2013, coordinated by the Centre for Cancer Detection (CCD) in cooperation with the Belgian Cancer Registry (BCR). The CCD offers a biennial faecal immunochemical test (FIT) to Flemish citizens aged 56-74 years and recommends a colonoscopy when screened positive by FIT. The study objective is to investigate sociodemographic differences in follow-up colonoscopy adherence after a positive FIT.

METHODS

Characteristics of the study population were derived by linkage of data from the CCD and BCR, linked with data of the Intermutualistic Agency and the Crossroads Bank for Social Security, resulting in aggregated tables to ensure anonymity. A total of 37 834 men and women aged 56-74 years with a positive FIT in 2013-2014 were included. Adherence to follow-up colonoscopy was calculated for age, sex, work intensity at household level, preferential reimbursement status, and first and current nationality. Descriptive analyses and logistic regressions were performed.

RESULTS

Nonadherence to follow-up colonoscopy was associated with increasing age, and was significantly higher in men [odds ratio (OR), 1.08], participants with a preferential reimbursement status (OR, 1.34), very low work intensity (OR, 1.41), no payed work (OR, 1.38) and other than Belgian nationality by birth (OR, 1.6-4.66).

CONCLUSION

Adherence to follow-up colonoscopy after a positive FIT differs according to sociodemographic variables. Additional research is needed to explore reasons for nonadherence to colonoscopy and tackle barriers by exploring interventions to increase colonoscopy follow-up adherence after a positive FIT in the Flemish colorectal cancer screening programme.

Perceived life expectancy and colorectal cancer screening intentions and behaviour: A population-based UK study

The relationships between perceived life expectancy (PLE), cancer screening intentions and behaviour are not well understood, despite the importance of remaining life expectancy for the early diagnosis benefits of screening. This study investigates the relationships between PLE and each of: the intention to complete faecal occult blood test (FOBt) screening, ‘ever’ uptake of FOBt screening, and repeat uptake of FOBt screening for colorectal cancer. Data were from the population-representative Attitudes, Behaviour and Cancer UK Survey II (ABACUS II) in England in 2015. Eligible respondents for the present analysis were aged 60–70 years (FOBt eligible age range), who completed the survey question on perceived life expectancy (N = 824). We used logistic regression models to estimate the associations between PLE and the intention to complete screening, ‘ever’ uptake of screening, and repeat uptake of screening, with adjustment for age, gender, occupation-based social grade, marital status, ethnicity, and smoking status. PLE was positively associated with repeated uptake of FOBt (adjusted OR = 2.55; 95% CI: 1.04–6.30 for expecting to live to ≥90 years versus <80 years). Older adults may base decisions to continually participate in cancer screening on their expectations of remaining life expectancy. Future research should investigate the feasibility and acceptability of individualised cancer screening recommendations that take life expectancy into account.

Return to bowel screening after a false-positive faecal immunochemical test in BowelScreen (the National Bowel Screening Programme in Ireland)

Objective

Little research exists on what predicts individual return to screening after a false-positive faecal immunochemical test in a population bowel screening programme. We aimed to quantify the impact of false-positive faecal immunochemical test in the first round of screening on re-attendance in BowelScreen, the National Bowel Screening Programme in Ireland.

Methods

A retrospective cohort study was conducted. False-positivity was defined as a positive faecal immunochemical test with subsequent colonoscopy showing no evidence of malignancy or surveillance requirement. In those with a false-positive faecal immunochemical test, logistic regression was used to predict repeat participation in the second round.

Results

Of 196,149 individuals who attended the first screening round, 108,075 were eligible and re-invited in the second round, and 93,971 accepted the invitation (86.9%). Second round uptake was higher in faecal immunochemical test-negative individuals compared with those having false-positive results (87.5% vs. 73.1%; p < 0.001). Older age (odds ratio (OR) 0.75; 95% confidence interval (CI) 0.60–0.94), computed tomography colonography (unsuitability/failed colonoscopy) (OR 0.40; 95% CI 0.21–0.73), and longer duration from screening invitation to faecal immunochemical test result (OR 0.991; 95% CI 0.9872–0.995) were predictors of non-re-attendance in the next screening round.

Conclusion

There is a significant reduction in re-attendance rates for individuals with false-positive faecal immunochemical test results. The letter sent following a negative colonoscopy is being reviewed to ensure that it provides adequate encouragement to re-attend. There are roles for screening promotion and for Gastroenterologists and Advanced Nurse Practitioners to emphasize the importance of regular faecal immunochemical tests after a negative colonoscopy.

Factors related to the participation and detection of lesions in colorectal cancer screening programme-based faecal immunochemical test

Background

The overall aim of this study was to describe trends in participation rates and detection of lesions in a colorectal cancer (CRC) screening programme, during three rounds, using faecal immunochemical test (FIT).

Methods

National registers were used to collect data on invitations for CRC screening in the Basque Country (Spain) from 2009 to 2014. Information about participation, age, gender and lesions in each round were collected.

Results

A total of 961.533 individuals were included in the analysis; respectively, 584.950, 298.143 and 78.440 in the first, second and third rounds. The average participation rate was 68.4% (66.8, 70.4 and 72.3%, respectively by round; P < 0.001) and the positivity rate was 6.3% (7, 5.5 and 5.4%, respectively by round; P < 0.001). The participation rate increased significantly with age and was found to be higher in women versus men. A total of 15.144 advanced adenomas and 2.131 CRCs were diagnosed, leading to a detection rate of 23.9 and 3.4‰, respectively. Regarding gender, men had the highest rates in all periods and rounds. The detection rate of advanced neoplasia was lower in the regular when compared with irregular paricipants.

Conclusions

In a CRC screening, this organization obtained high FIT participation rates. Older participants and women were associated with a higher participation. The detection rate of lesions was higher in men, independent on age and round.

Longitudinal Adherence to Immunochemical Fecal Occult Blood Testing vs Guaiac-based FOBT in an Organized Colorectal Cancer Screening Program

Longitudinal adherence is a critical component of the efficacy of stool-based screening programs because they should be repeated every 1-2 years. Few data have been published on the uptake in multiple rounds of fecal occult blood test-based (FOBT) colorectal cancer (CRC) screening. We calculated two measures of longitudinal adherence to biennial FOBT (guaiac fecal occult blood test:gFOBT or fecal immunochemical test:FIT) to better understand its impact on the programmatic effectiveness of a population-based CRC screening program (2000-2017). Ongoing population-based CRC program of men and women aged 50-69 years. Variables: Age at first CRC screening invitation, sex, number of screening invitations, number of screens, deprivation score, and uptake rate. Logistic regression models were used to assess the independent effect of sex, age at first invitation, deprivation, and the type of screening test offered on adherence. The uptake rate for guaiac fecal occult blood test (gFOBT) was 23.9%, and for the fecal immunochemical test (FIT), it was 37.4%. The overall rate of consistently screened invitees after seven rounds of screening was 14.2%, being 20.6% for those individuals who used FIT and 14.3% for those who used gFOBT. Factors associated with continued participation (consistent vs. inconsistent screenees) showed that the longitudinal adherence was associated with age, screening test used, and number of invitations. Continued participation was lower in individuals who were screened using FIT than among those screened using gFOBT [OR, 0.68; 95% confidence interval (CI), 0.57-0.81]. The overall rate of consistently screened invitees for colorectal cancer screening was higher with FIT than gFOBT. Studying the rate of individuals being current for screening may help to anticipate potential benefits before the long-term outcome data are available.

Factors related to longitudinal adherence in colorectal cancer screening: qualitative research findings

BACKGROUND

The effectiveness of screening in colorectal cancer prevention depends on sustained participation rates. The objective of this study was to explore factors related to the longitudinal adherence of screening behavior in the context of a biennial population-based cancer screening program.

METHODS

Eight focus groups were conducted with individuals who were invited two or three consecutive times to a population-based colorectal cancer screening program using a fecal occult blood test and who agreed to participate in the program at least once (n = 45). The criteria used to select the study members included adherence to fecal occult blood test maintenance, factors regarding their initial participation in the colorectal cancer screening, sex, and contextual educational level.

RESULTS

The participants expressed a high level of satisfaction with the program; however, they showed a low level of understanding with respect to cancer screening. Consulting a general practitioner was cited by all participants as an important factor that mediated their final decision or influenced their behavior as a whole with regard to the program. Fear played a different role in the screening behavior for regular and irregular adherent participants. In the adherent participants, fear facilitated their continued participation in the screening program, whereas for the irregular participants, fear led them to avoid or refuse further screening. Having a close person diagnosed with colorectal cancer was a facilitator for the regular adherent participants. The irregular adherent participants showed some relaxation with respect to screening after a negative result and considered that further screening was no longer necessary.

CONCLUSION

Considering the importance of primary healthcare professionals in the decision regarding sustained participation, it is important to better engage them with cancer screening programs, as well as improve the communication channels to provide accurate and balanced information for both health professionals and individuals.

Patterns of participation over four rounds of annual fecal immunochemical test-based screening for colorectal cancer: what predicts rescreening?

BACKGROUND

Participation at the recommended intervals is critical for screening to be effective in reducing colorectal cancer (CRC) incidence. This study describes patterns of screening participation over four rounds of fecal immunochemical testing (FIT) to identify whether demographic variables and prior screening satisfaction are significantly associated with patterns of re-participation.

METHODS

Baseline surveys were mailed to 4000 South Australians randomly selected from the electoral-roll. Respondents (n = 1928/48.2%) were offered four annual FIT rounds. Screening participation and satisfaction at each round were recorded.

RESULTS

Study participation was 58.5, 66.9, 73.1 and 71.4% respectively over four rounds. Three participation patterns were described: consistent participation (43.1%), consistent non-participation (26.4%) and inconsistent participation (changeable; 30.5%), including intermittent and sustained change patterns. Sustained change described those who changed participatory behavior and then maintained for at least two rounds (n = 375/19.5%). Older people, and those not working were most likely to sustain participation. Younger invitees, especially men, were more likely to change participatory behavior and sustain the change. People with higher disadvantage, less education, not working and with no prior (pre-trial) screening experience were more likely to start participating and drop out. People dissatisfied with a prior screening test, including finding aspects embarrassing or unpleasant, were also more likely not to participate in annual screening or to drop out.

CONCLUSIONS

The findings identify those at risk of non- or inconsistent participation in rescreening. They should aid targeting of interventions for demographic groups at risk and ensuring screening experiences are not perceived as unpleasant or difficult.

Text-message Reminders in Colorectal Cancer Screening (TRICCS): a randomised controlled trial

BACKGROUND

We investigated the effectiveness of a text-message reminder to improve uptake of the English Bowel Cancer Screening programme in London.

METHODS

We performed a randomised controlled trial across 141 general practices in London. Eight thousand two hundred sixty-nine screening-eligible adults (aged 60-74 years) were randomised in a 1 : 1 ratio to receive either a text-message reminder (n=4134) or no text-message reminder (n=4135) if they had not returned their faecal occult blood test kit within 8 weeks of initial invitation. The primary outcome was the proportion of adults returning a test kit at the end of an 18-week screening episode (intention-to-treat analysis). A subgroup analysis was conducted for individuals receiving an invitation for the first time.

RESULTS

Uptake was 39.9% in the control group and 40.5% in the intervention group. Uptake did not differ significantly between groups for the whole study population of older adults (adjusted odds ratio (OR) 1.03, 95% confidence interval (CI) 0.94-1.12; P=0.56) but did vary between the groups for first-time invitees (uptake was 34.9% in the control and 40.5% in the intervention; adjusted OR 1.29, 95% CI 1.04-1.58; P=0.02).

CONCLUSIONS

Although text-message reminders did not significantly increase uptake of the overall population, the improvement among first-time invitees is encouraging.

Adherence to colorectal cancer screening: four rounds of faecal immunochemical test-based screening

BACKGROUND

The effectiveness of faecal immunochemical test (FIT)-based screening programs is highly dependent on consistent participation over multiple rounds. We evaluated adherence to FIT screening over four rounds and aimed to identify determinants of participation behaviour.

METHODS

A total of 23 339 randomly selected asymptomatic persons aged 50-74 years were invited for biennial FIT-based colorectal cancer screening between 2006 and 2014. All were invited for every consecutive round, except for those who had moved out of the area, passed the upper age limit, or had tested positive in a previous screening round. A reminder letter was sent to non-responders. We calculated participation rates per round, response rates to a reminder letter, and differences in participation between subgroups defined by age, sex, and socioeconomic status (SES).

RESULTS

Over the four rounds, participation rates increased significantly, from 60% (95% CI 60-61), 60% (95% CI 59-60), 62% (95% CI 61-63) to 63% (95% CI 62-64; P for trend<0.001) with significantly higher participation rates in women in all rounds (P<0.001). Of the 17 312 invitees eligible for at least two rounds of FIT screening, 12 455 (72%) participated at least once, whereas 4857 (28%) never participated; 8271 (48%) attended all rounds when eligible. Consistent participation was associated with older age, female sex, and higher SES. Offering a reminder letter after the initial invite in the first round increased uptake with 12%; in subsequent screening rounds this resulted in an additional uptake of up to 10%.

CONCLUSIONS

In four rounds of a pilot biennial FIT-screening program, we observed a consistently high and increasing participation rate, whereas sending reminders remain effective. The substantial proportion of inconsistent participants suggests the existence of incidental barriers to participation, which, if possible, should be identified and removed.

Factors associated with completion of bowel cancer screening and the potential effects of simplifying the screening test algorithm

Background:

The primary colorectal cancer screening test in England is a guaiac faecal occult blood test (gFOBt). The NHS Bowel Cancer Screening Programme (BCSP) interprets tests on six samples on up to three test kits to determine a definitive positive or negative result. However, the test algorithm fails to achieve a definitive result for a significant number of participants because they do not comply with the programme requirements. This study identifies factors associated with failed compliance and modifications to the screening algorithm that will improve the clinical effectiveness of the screening programme.

Methods:

The BCSP Southern Hub data for screening episodes started in 2006–2012 were analysed for participants aged 60–69 years. The variables included age, sex, level of deprivation, gFOBt results and clinical outcome.

Results:

The data set included 1 409 335 screening episodes; 95.08% of participants had a definitively normal result on kit 1 (no positive spots). Among participants asked to complete a second or third gFOBt, 5.10% and 4.65%, respectively, failed to return a valid kit. Among participants referred for follow up, 13.80% did not comply. Older age was associated with compliance at repeat testing, but non-compliance at follow up. Increasing levels of deprivation were associated with non-compliance at repeat testing and follow up. Modelling a reduction in the threshold for immediate referral led to a small increase in completion of the screening pathway.

Conclusions:

Reducing the number of positive spots required on the first gFOBt kit for referral for follow-up and targeted measures to improve compliance with follow-up may improve completion of the screening pathway.

Social Cognitive Mediators of Sociodemographic Differences in Colorectal Cancer Screening Uptake

Background. This study examined if and how sociodemographic differences in colorectal cancer (CRC) screening uptake can be explained by social cognitive factors. Methods. Face-to-face interviews were conducted with individuals aged 60–70 years (n = 1309) living in England as part of a population-based omnibus survey. Results. There were differences in screening uptake by SES, marital status, ethnicity, and age but not by gender. Perceived barriers (stand. b = −0.40, p < 0.001), social norms (stand. b = 0.33, p < 0.001), and screening knowledge (stand. b = 0.17, p < 0.001) had independent associations with uptake. SES differences in uptake were mediated through knowledge, social norms, and perceived barriers. Ethnic differences were mediated through knowledge. Differences in uptake by marital status were primarily mediated through social norms and to a lesser extent through knowledge. Age differences were largely unmediated, except for a small mediated effect via social norms. Conclusions. Sociodemographic differences in CRC screening uptake were largely mediated through social cognitive factors. Impact. Our findings suggest that multifaceted interventions might be needed to reduce socioeconomic inequalities. Ethnic differences might be reduced through improved screening knowledge. Normative interventions could emphasise screening as an activity endorsed by important others outside the immediate family to appeal to a wider audience.

Micro actions in colorectal cancer screening participation: a population-based survey study

Background

Low uptake of colorectal cancer (CRC) screening is a cause for concern. This study explored people’s anticipated response to receiving the test kit to shed light on past screening uptake and help inform future interventions to increase participation.

Methods

Face-to-face interviews were conducted with respondents living in England who were eligible for CRC screening as part of a population-based ‘omnibus’ survey. Respondents were asked what they would do (‘micro actions’) if they received a CRC screening test kit through the mail (apart from completing it or not), and their unprompted responses were coded (multiple codes allowed). Past ‘ever’ uptake and screening intention were also recorded. The final analysis included 1237 respondents aged 60–70.

Results

Respondents who said that they would decide after some thought’ (p < .001), ‘put [it] aside to deal with later’ (p < .001), ‘put it on the “to do list/ pile”’ (p < .05) or ‘discuss it with a health care professional’ (p < .01) had decreased odds of having participated. Those who said they would ‘read the instruction leaflet’ (p < .001), ‘put the kit near the toilet’ (p < .001) or ‘decide when to do the test’ (p < .05) were more likely to have taken part in CRC screening. With the exception of ‘decide when to do the test’ and ‘discuss it with a health care professional’, all associations with past uptake remained significant after adjusting for other micro actions and screening intention. ‘Make a note somewhere (to remind myself)’ was mentioned by less than 1 % of respondents.

Conclusions

Delay-causing and preparatory micro actions were associated with past CRC screening uptake. Self-regulatory micro actions (e.g. making a note to remind oneself) were rarely mentioned as responses to receiving a screening invitation. Interventions aimed at reducing delay and facilitating preparatory and self-regulatory behaviours might help increase uptake. The behaviour-focused survey method is a promising avenue for future health behaviour research.