Exploring the validity of the continuum of resistance model for discriminating early from late and non-uptake of colorectal cancer screening: implications for the design of invitation and reminder letters

Examining the continuum of resistance model in two population-based screening studies in Sweden

In studies recruited on a voluntary basis, lack of representativity may impair the ability to generalize findings to the target population. Previous studies, primarily based on surveys, have suggested that generalizability may be improved by exploiting data on individuals who agreed to participate only after receiving one or several reminders, as such individuals may be more similar to non-participants than what early participants are. Assessing this idea in the context of screenings, we compared sociodemographic characteristics and health across early, late, and non-participants in two large population-based screening studies in Sweden: STROKESTOP II (screening for atrial fibrillation; 6,867 participants) and SCREESCO (screening for colorectal cancer; 39,363 participants). We also explored the opportunities to reproduce the distributions of characteristics in the full invited populations, either by assuming that the non-participants were similar to the late participants, or by applying a linear extrapolation model based on both early and late participants. Findings showed that early and late participants exhibited similar characteristics along most dimensions, including civil status, education, income, and health examination results. Both these types of participants in turn differed from the non-participants, with fewer married, lower educational attainments, and lower incomes. Compared to early participants, late participants were more likely to be born outside of Sweden and to have comorbidities, with non-participants similar or even more so. The two empirical models improved representativity in some cases, but not always. Overall, we found mixed support that data on late participation may be useful for improving representativeness of screening studies.

Factors influencing organised faecal occult blood test screening participation in culturally and linguistically diverse populations: a scoping review

OBJECTIVE

This review aims to provide a comprehensive overview of the literature examining factors influencing participation in organised faecal occult blood test (FOBT) screening programmes in culturally and linguistically diverse populations. This article addresses gaps in the literature by providing a mixed methods review of the multilevel influences on FOBT screening in culturally and linguistically diverse (CALD) populations. This review was guided by the question "What are the factors influencing participation in organised FOBT screening programs in CALD populations?"

STUDY DESIGN

Scoping review.

METHODS

A scoping review methodology was used to summarise the available evidence. A thematic analysis of the included studies was undertaken to identify factors influencing organised FOBT screening participation in CALD populations from the literature.

RESULTS

FOBT screening participation was lower by ethnicity, religion, birthplace and language spoken. Barriers to screening included, faecal aversion, fatalism, fear of cancer, language and literacy barriers, difficulty accessing translated materials and low colorectal screening knowledge and awareness. CALD populations also had lower perceived benefits, susceptibility and cues to action, higher perceived barriers and greater perceived external health locus control than non-CALD populations. Facilitators of screening included positive attitudes to screening, general practitioner recommendations and social support. Group education sessions and narrative-based screening information were found to increase screening participation.

CONCLUSION

This review highlights the range of interrelated factors influencing participation in organised FOBT screening programmes in CALD populations and proposes multicomponent interventions to address low screening uptake. Features of successful community-level interventions should be explored further. Narratives show promise for engaging CALD populations. Accessibility of screening information should be addressed at the system level. Leveraging the general practitioner relationship in promoting FOBT screening programmes may also be an effective strategy to target 'hard-to-reach' populations.

The Effects of the Nurse Navigation Program in Promoting Colorectal Cancer Screening Behaviors: a Randomized Controlled Trial

Although screening programs are known and recommended for the early detection of colorectal cancer (CRC), the screening rates for the fecal occult blood test (FOBT) and colonoscopy are very low among adult individuals. Navigation programs, also known as individualized counseling, have recently begun to be used for increasing screening rates. The purpose of this study was to compare the efficacy of the Nurse Navigation Program versus usual care on CRC screening participation and movement in stage of adoption for CRC screening and to examine perceived benefits of and barriers to CRC screening. This study was designed in line with a pre- and posttest two-group methodology. A total of 110 participants (55 nurse-navigated and 55 non-navigated patients) were studied. Data were collected using the following three tools: a sociodemographic information form, the Harvard Colorectal Cancer Risk Assessment Tool, and Instruments to Measure Colorectal Cancer Screening Benefits and Barriers. Following the Nurse Navigation Program, the FOBT (82 and 84%, respectively) and colonoscopy completion rates (15 and 22%, respectively) were significantly higher in the nurse-navigated group than in the non-navigated group at 3 and 6 months follow-up. Following the program, the benefit perceptions of the nurse-navigated group about CRC screening were improved, and their barrier perceptions were reduced. The results showed that the Nurse Navigation Program had significant effects on CRC screening behavior and health-related beliefs concerning CRC screening. Further assessment of the Nurse Navigation Program in different groups should be performed to observe its effects.

The effects of reminders for colorectal cancer screening: participation and inequality

PURPOSE

To investigate the effect of sending out reminders for colorectal cancer screening on socioeconomic and demographic inequalities in screening uptake.

METHODS

All citizens aged 50-74 in Denmark are invited every 2 years for colorectal cancer screening. Non-participants receive an electronically distributed reminder. Data for these analyses were derived from national registers. Socioeconomic status was measured by income and educational level. Demographic variables included age, gender and marital status, and the analyses were stratified by immigration status. Logistic regression analyses were conducted to estimate the odds of non-participation for invited citizens and for reminded citizens divided by socioeconomic and demographic predictors.

RESULTS

Of 763,511 native Danes invited for screening from 2014 to 2015, 387,116 (50.70%) participated after the initial invitation and 133,470 after receiving a reminder. Differences in participation were present in relation to all subgroups among both the invited citizens and reminded citizens. Differences persisted after full model adjustments with reductions for demographic variables. Odds ratio (OR) for non-participation in the eldest age group was 0.32 (95% CI, 0.32; 0.33) before and 1.11 (95% CI 1, 0.08; 1.14) after the reminder, compared to those under 55 years. OR for the 4th income quartile was 0.54 (95% CI, 0.53; 0.55) before and 0.44 (95% CI, 0.43; 0.45) after the reminder, compared to 1st quartile.

CONCLUSIONS

Reminders increased the overall participation, and the inequalities in participation in relation to demographic factors were reduced after the distribution of reminders. The age differences were especially reduced. The inequalities in participation related to socioeconomic status were, however, slightly increased after reminder distribution.

A Blood Test for Methylated BCAT1 and IKZF1 vs. a Fecal Immunochemical Test for Detection of Colorectal Neoplasia

Objectives:

To compare the performance of a new blood test for colorectal cancer (CRC) to an established fecal immunochemical test (FIT) in a study population with the full range of neoplastic and non-neoplastic pathologies encountered in the colon and rectum.

Methods:

Volunteers were asked to complete a FIT prior to colonoscopy. Blood was collected after bowel preparation but prior to colonoscopy, and plasma was assayed for the presence of methylated BCAT1 and IKZF1 DNA using a multiplex real-time PCR assay. Sensitivity and specificity estimates for the blood test were calculated from true- and false-positive rates for neoplasia and compared with FIT at a range of fecal hemoglobin (Hb) concentration positivity thresholds.

Results:

In total, 1,381 volunteers (median age 64 years; 49% male) completed both tests prior to colonoscopy. Estimated sensitivity of the BCAT1/IKZF1 blood test for CRC was 62% (41/66; 95% confidence interval 49–74%) with a specificity of 92% (1207/1315; 90–93%). FIT returned the same specificity at a cutoff of 60 μg Hb/g, at which its corresponding sensitivity for cancer was 64% (42/66; 51–75%). In the range of commonly used FIT cutoffs, respective cancer sensitivity and specificity estimates with FIT were: 59% (46–71%) and 93% (92–95%) at 80 μg Hb/g, and 79% (67–88%) and 81% (78–83%) at 10 μg Hb/g. Although estimated sensitivities were not significantly different between the two tests for any stage of cancer, FIT showed a significantly higher sensitivity for advanced adenoma at the lower cutoffs. Specificity of FIT, but not of the BCAT1/IKZF1 blood test, deteriorated substantially in people with overt blood in the feces. When combining FIT (cutoff 10 μg Hb/g) with the BCAT1/IKZF1 blood test, sensitivity for cancer was 89% (79–96%) at 74% (72–77%) specificity.

Conclusions:

A test based on detection of methylated BCAT1/IKZF1 DNA in blood has comparable sensitivity but better specificity for CRC than FIT at the commonly used positivity threshold of 10 μg Hb/g. Further evaluation of the new test relative to FIT in the population screening context is now required to fully understand the potential advantages and disadvantages of these biomarkers in screening.