Scottish Bowel Screening Programme Research Articles

Interval cancers in a national colorectal screening programme based on faecal immunochemical testing: Implications for faecal haemoglobin concentration threshold and sex inequality.

To compare interval cancer proportions (ICP) in the faecal immunochemical test (FIT)-based Scottish Bowel Screening Programme (SBoSP) with the former guaiac faecal occult blood test (gFOBT)-based SBoSP and investigate associations between interval cancer (IC) and faecal haemoglobin concentration (f-Hb) threshold, sex, age, deprivation, site, and stage. The ICP data from first year of the FIT-based SBoSP and the penultimate year of the gFOBT-based SBoSP were compared in a prospective cohort design. With FIT, 801 colorectal cancers (CRCs) were screen detected (SDC), 802 were in non-participants, 548 were ICs, 39 were colonoscopy missed and 72 were diagnosed after incomplete screening; with gFOBT: 540, 904, 556, 45, and 13, respectively. FIT had a significantly higher proportion of SDC compared to IC than gFOBT. For FIT and gFOBT, ICP was significantly higher in women than men. As f-Hb threshold increased, ICP increased and, for any f-Hb threshold for men, a lower threshold was required for comparable ICP in women. In Scotland, the current threshold of ≥80 µg Hb/g faeces would have to be lowered to ≥40 µg Hb/g faeces for women to achieve sex equality for ICP. In the FIT-based SBoSP, there were four times as many stage I SDC than IC. This was reversed in advanced stages, with twice as many stage IV CRC diagnosed as IC versus SDC. Reducing the numbers of IC requires lowering the f-Hb threshold. Using different f-Hb thresholds for women and men could eliminate the sex disparity, but with additional colonoscopy.

Improved use of faecal immunochemical tests for haemoglobin in the Scottish bowel screening programme.

This study aimed to develop a risk-scoring model in the Scottish Bowel Screening Programme incorporating faecal haemoglobin concentration with other risk factors for colorectal cancer. Data were collected for all individuals invited to participate in the Scottish Bowel Screening Programme between November 2017 and March 2018 including faecal haemoglobin concentration, age, sex, National Health Service Board, socioeconomic status, and screening history. Linkage with The Scottish Cancer Registry identified all screening participants diagnosed with colorectal cancer. Logistic regression was performed to identify which factors demonstrated significant association with colorectal cancer and could be used in the development of a risk-scoring model. Of 232,076 screening participants, 427 had colorectal cancer: 286 diagnosed following a screening colonoscopy and 141 arising after a negative screening test result giving an interval cancer proportion of 33.0%. Only faecal haemoglobin concentration and age showed a statistically significant association with colorectal cancer. Interval cancer proportion increased with age and was higher in women (38.1%) than men (27.5%). If positivity in women were mirrored in men at each age quintile interval cancer proportion would still have remained higher in women (33.2%). Moreover, an additional 1201 colonoscopies would be required to detect 11 colorectal cancers. Development of a risk scoring model using early data from the Scottish Bowel Screening Programme was not feasible due to most variables showing insignificant association with colorectal cancer. Tailoring the faecal haemoglobin concentration threshold according to age could help to diminish some of the disparity in interval cancer proportion between women and men. Strategies to achieve sex equality using faecal haemoglobin concentration thresholds depend considerably on which variable is selected for equivalency and this requires further exploration.

Increasing uptake of FIT colorectal screening: protocol for the TEMPO randomised controlled trial testing a suggested deadline and a planning tool

IntroductionScreening can reduce deaths from colorectal cancer (CRC). Despite high levels of public enthusiasm, participation rates in population CRC screening programmes internationally remain persistently below target levels. Simple behavioural interventions...

What are common barriers and helpful solutions to colorectal cancer screening? A cross-sectional survey to develop intervention content for a planning support tool

ObjectiveColorectal screening using faecal immunochemical tests (FITs) can save lives if the people invited participate. In Scotland, most people intend to complete a FIT but this is not reflected in...

Do faecal test-based colorectal cancer screening pilots provide data that are reflected in subsequent programmes? Evidence from interval cancer proportions.

Guidelines on colorectal cancer (CRC) screening with guaiac faecal occult blood tests (gFOBTs) and faecal immunochemical tests (FITs) include the need for a pilot before a programme is introduced. Interval cancers (ICs), cancers arising after a negative screening test result but before the next scheduled invite, are important indicators of programme quality. Our aim was to compare IC in the gFOBT-based Scottish Bowel Screening Programme (SBoSP), a FIT-based pilot, and the FIT-based SBoSP, to assess if the pilot provided data that was reflected in the subsequent programme. The IC proportions (ICPs) data ([IC/(IC + screen detected CRC)] x 100) from the penultimate year of the gFOBT-based SBoSP, the 6-month pilot and the first year of the FIT-based SBoSP were compared. To ensure appropriate comparison, these data were only from the two pilot NHS Boards. For all participants, and females and males, the ICPs were very similar in the gFOBT-based SBoSP and the pilot. The faecal haemoglobin concentration (f-Hb) threshold for the pilot was set at ≥80μg Hb/g faeces. However, in marked contrast, in the FIT-based SBoSP, at the same threshold, the ICPs were lower. In all three groups, the ICPs were higher in females than in males. Data on variables in pilots, including ICP, can be informative, but only if variables such as FIT system are held consistent between pilot and programme. Lowering the f-Hb threshold for females to give the same ICP as males might be a strategy to minimise sex inequality.

Relationship between BMI, CT-derived body composition and colorectal neoplasia in a bowel screening population.

IntroductionObesity is associated with an increased risk of colorectal cancer (CRC). Unlike the indirect measures such as BMI, CT-Body composition (CT-BC) allows for the assessment of both volume and distribution of adipose tissue. Therefore, the aim of this study was to examine the relationship between host characteristics, BMI, CT-BC measurements and the incidence of colorectal neoplasia.MethodsPatients undergoing CT Colonography (CTC) as part of the Scottish Bowel Screening Programme, between July 2009 and February 2016, were eligible for inclusion. Data were collected including demographic data, clinicopathological variables and CT-BC measurements including skeletal muscle index (SMI), subcutaneous fat index (SFI) and visceral fat area (VFA). CTC, colonoscopy, and pathology reports were used to identify CRC incidence. Associations between demographic data, clinicopathological variables, CT-BC measurements, colorectal neoplasia and advanced colorectal neoplasia were analysed using univariate and multivariate binary logistics regression.Results286 patients met the inclusion criteria. Neoplasia was detected in 105 (37%) of the patients with advanced neoplasia being detected in 72 (69%) of patients. On multivariate analysis sex (p < 0.05) and high VFA (p < 0.001) remained independently associated with colorectal neoplasia. On multivariate analysis a high SFI (p < 0.01) remained independently associated with advanced colorectal neoplasia. BMI was not associated with either colorectal neoplasia or advanced colorectal neoplasia.ConclusionWhen directly compared to BMI, CT derived fat measurements were more closely associated with the degree of neoplasia in patients undergoing colorectal cancer screening. In patients investigated with CT colonography, CT adipose measures may stratify the risk and grade of neoplasia.

Faecal haemoglobin concentrations in women and men diagnosed with colorectal cancer in a national screening programme

ObjectiveThere is evidence that colorectal cancer screening using faecal haemoglobin is less effective in women than men. The faecal haemoglobin concentrations were therefore examined in women and men with screen-detected colorectal cancer.SettingScottish Bowel Screening Programme, following the introduction of a faecal immunochemical test from November 2017, to March 2020.MethodsData were collated on faecal haemoglobin concentrations, pathological stage and anatomical site of the main lesion in participants who had colorectal cancer detected. The data in women and men were compared.ResultsFor the faecal haemoglobin concentrations studied (>80 µg Hb/g faeces), the distributions indicated lower concentrations in women. Marked differences were found between women and men diagnosed with colorectal cancer. The median faecal haemoglobin concentration for women (n = 720) was 408 µg Hb/g faeces compared to 473 µg Hb/g faeces for men (n = 959) (p = 0.004) and 50.6% of the results were >400 µg Hb/g faeces in women; in men, this was 57.8%. The difference in faecal haemoglobin concentrations in women and men became less statistically significant as stage advanced from stages I–IV. For right-sided, left-sided and rectal colorectal cancer, a similar gender difference persisted in all sites. Differences in faecal haemoglobin between the genders were significant for left-sided cancers and stage I and approached significance for rectal cancers and stage II, but all sites and stages showed lower median faecal haemoglobin concentrations for women.ConclusionsTo minimise gender inequalities, faecal immunochemical test-based colorectal cancer screening programmes should evaluate a strategy of using different faecal haemoglobin concentration thresholds in women and men.

SP1.1.17The relationship between colorectal neoplasia and body composition in a bowel screening population

Abstract Aims Conflicting evidence exists as to the effect of elevated BMI in the development of colorectal neoplasia. Yet BMI is a crude measure of adiposity. The present study investigates the association between CT derived measures of body composition including sarcopenia, subcutaneous fat index (SFI) and visceral obesity and colorectal neoplasia. Methods 358 consecutive patients undergoing CT virtual colonoscopy (CTC) as part of the Scottish Bowel Screening Programme were eligible for inclusion. Demographic data and the above measures body composition were calculated using previously published CT derived methods. Medical records were examined for colonoscopic findings and pathology reports. Results 121/358 (34%) were males. Median age 65. 126/358 (35%) patients were found to have a colorectal neoplasia. 84/126 (67%) had advanced neoplasia. 26/358 (7%) had adenocarcinoma. On multivariable analysis, both male sex and visceral obesity was associated with the presence of colorectal neoplasia, OR 2.62, [95% CI 1.51-4.55, p = 0.001] and OR 2.83, {95% CI 1.25-6.41, p = 0.01] respectively. The relationship was dose dependent with an increased risk of colorectal neoplasia in the 3rd [OR 2.13 95% CI 1.09-4.14 p &amp;lt; 0.05] and 4th [OR 3.77 95% CI 1.96-7.26 p &amp;lt; 0.001] quartiles of visceral fat area. BMI, SFI and sarcopenia were not associated with colorectal neoplasia in the present study. Conclusions Male sex and in particular, visceral obesity is associated with increased risk of colorectal neoplasia. In addition to the known cardiovascular and metabolic dangers of visceral obesity, the present work suggests that visceral obesity may also play a role in colorectal neoplasia formation.

TP1.2.4The incidence, implications and risk factors for extracolonic findings at CT colonography in a bowel screening population

Abstract Aim CT virtual colonoscopy (CTC) is increasingly relied upon in bowel screening programmes. Concern remains regarding the prevalence of incidental extra-colonic findings (ECF). The present study reports on the prevalence and implications of ECF as part of a UK bowel screening programme. Methods Reports for 400 consecutive CTCs carried out as part of the Scottish Bowel Screening Programme were examined. Intra and extracolonic findings were recorded using the CT Colonography Reporting and Data System (C-RADS). Medical records pertaining to ECF follow-up were examined. Cost analysis was performed. Results 394 patients were included. 146 (37%) were males. Median age was 65 years, median follow-up was 72 months (Range 32-110). 92 (23%) patients had CTC as their primary investigation, 302 (77%) patients underwent CTC due to failed colonoscopy. Overall, 244/394 (62%) patients had ECF with only 45/394 (11%) found to have colonic pathology. 65/394 (16%) had moderately or highly significant ECF, (C-RADS E3-4). Of the 244 patients with ECF, 59 (24%) underwent further investigation, estimated cost £17,589. The majority, 37/59 (63%) were found to have benign disease after follow-up. Conclusion ECF at CTC are more frequent than colonic findings. The majority of ECF investigated are found to be benign yet a quarter of ECF are further investigated at a cost to the health service and the patient. Clinicians should be judicial when ordering and consenting patients with regards ECF and its implications if CTC is considered. Particularly when the test is part of a public funded and voluntary screening programme.

The inflammatory microenvironment in screen-detected premaligant adenomatous polyps: early results from the integrated technologies for improved polyp surveillance (INCISE) project.

Around 40% of patients who attend colonoscopy following a positive stool screening test have adenomatous polyps. Identifying which patients have a higher propensity for malignant transformation is currently poorly understood. The aim of the present study was to assess whether the type and intensity of inflammatory infiltrate differ between screen-detected adenomas with high-grade dysplasia (HGD) and low-grade dysplasia (LGD). A representative sample of 207 polyps from 134 individuals were included from a database of all patients with adenomas detected through the first round of the Scottish Bowel Screening Programme in NHS Greater Glasgow and Clyde (April 2009-April 2011). Inflammatory cell phenotype infiltrate was assessed by immunohistochemistry for CD3+, CD8+, CD45+ and CD68+ in a semi-quantitative manner at 20× resolution. Immune-cell infiltrate was graded as absent, weak, moderate or strong. Patient and polyp characteristics and inflammatory infiltrate were then compared between HGD and LGD polyps. CD3+ infiltrate was significantly higher in HGD polyps compared to LGD polyps (74 vs. 69%; P < 0.05). CD8+ infiltrate was significantly higher in HGD polyps compared to LGD polyps (36 vs. 13%; P < 0.001) whereas CD45+ infiltrate was not significantly different (69 vs. 64%; P = 0.401). There was no significant difference in CD68+ infiltrate (P = 0.540) or total inflammatory cell infiltrate (calculated from CD3+ and CD68+) (P = 0.226). This study reports an increase in CD3+ and CD8+ infiltrate in HGD colonic adenomas when compared to LGD adenomas. It may therefore have a use in the prognostic stratification and treatment of dysplastic polyps.

The impact of hypothetical PErsonalised Risk Information on informed choice and intention to undergo Colorectal Cancer screening colonoscopy in Scotland (PERICCS)\u2014a randomised controlled trial

BackgroundThere is currently no existing evidence on the effects of personalised risk information on uptake of colonoscopy following first line screening for colorectal cancer. This study aimed to measure the impact of providing risk information based on faecal haemoglobin concentration to allow a fully informed choice around whether or not to undergo colonoscopy.MethodsTwo thousand seven hundred sixty-seven participants from the Scottish Bowel Screening Programme (SBoSP) database, who had not recently been invited for screening, were randomised to receive one of three types of hypothetical risk information materials: (1) numerical risk information (risk categories of one in 40, one in 1600 and one in 3500), (2) categorical risk information (highest, moderate and lowest risk), or (3) positive screening result letter (control group). The primary outcome was the impact of the risk materials on intention to undergo colonoscopy, to allow comparison with the current colonoscopy uptake of 77% for those with a positive screening result in the SBoSP. Secondary outcomes were knowledge, attitudes and emotional responses to the materials.ResultsFour hundred thirty-four (15.7%) agreed to participate with 100 from the numerical risk group (69.0%), 104 from the categorical risk group (72.2%) and 104 from the control group (71.7%) returning completed materials. Intention to undergo colonoscopy was highest in the highest risk groups for the numerical and categorical study arms (96.8% and 95.3%, respectively), but even in the lowest risk groups was > 50% (58.1% and 60.7%, respectively). Adequate knowledge of colorectal screening and the risks and benefits of colonoscopy was found in ≥ 98% of participants in all three arms. All participants reported that they found the information easy-to-understand. 19.1%, 24.0% and 29.6% of those in the numerical, categorical and control group, respectively, reported that they found the information distressing (p > 0.05).ConclusionsApplying the risk categories to existing SBoSP data shows that if all participants were offered an informed choice to have colonoscopy, over two thirds of participants would intend to have the test. Equating to an increase in the number of screening colonoscopies from approx. 14,000 to 400,000 per annum, this would place an unmanageable demand on colonoscopy services, with a very small proportion of cancers and pre-cancers detected. However, the response to the materials were very positive, suggesting that providing risk information to those in lowest and moderate risk groups along with advice that colonoscopy is not currently recommended may be an option. Future research would be required to examine actual uptake.Trial registrationDate applied 1 December 2017 ISRCTN number 14254582.

Variation in changes in the incidence of colorectal cancer by age and association with screening uptake: an observational study

ObjectivesIn developed countries, the incidence of colorectal cancer (CRC) has declined in the over 50 years age group but increased in younger people. We studied CRC incidence by age and the influence of screening uptake.DesignAge-standardised and sex-standardised incidences for CRC from 1997 to 2017 were obtained from the Scottish Cancer Registry (SCR). In addition, linkage between the Scottish Bowel Screening Database and the SCR allowed investigation of any association between screening participation and CRC incidence.SettingScotland and the Scottish Bowel Screening Programme, in which guaiac faecal occult blood test screening was piloted from March 2000 and fully rolled by December 2009.ParticipantsFrom the introduction of screening in 2000 through to 2017, 2 395 172 were invited to participate, of whom 1 487 999 participated at least once.Main outcome measuresIncidence of CRC.ResultsIn the screening age range (50–74 years), CRC incidence peaked at 156.5 cases per 100 000 in 2010 after full roll-out of screening across Scotland but fell to 123.9 per 100 000 in 2017. However, under 50 years, there was a rise from 5.3 cases per 100 000 in 2000 to 6.8 per 100 000 in 2017. When CRC incidence was examined in those who had been offered screening, incidence fell in the participant group more than in the non-participant group after roll-out of screening was complete. Analysis of cumulative incidence demonstrated that CRC incidence in the participant group remained consistently below that of the non-participant from around 7 years of follow-up.ConclusionsThe incidence of CRC in Scotland has declined in the over 50 years age group but increased in younger people. It is likely that population screening has contributed to the reduction in CRC incidence in the over 50 years age group.

Faecal haemoglobin distributions by sex, age, deprivation and geographical region: consequences for colorectal cancer screening strategies.

Objectives Faecal immunochemical tests for haemoglobin (FIT) are becoming widely used in colorectal cancer (CRC) screening and assessment of symptomatic patients. Faecal haemoglobin concentration (f-Hb) thresholds are used to guide subsequent investigation. We established the distributions of f-Hb in a large screening population by sex, age, deprivation and geography. Methods Single estimates of f-Hb were documented for all individuals participating in the first 18 months of the Scottish Bowel Screening Programme (SBoSP). The distributions of f-Hb were generated for all participants, all men and women, and men and women by age quintile and deprivation quintile. Distributions were also generated by geographical region for all participants, men and women, and by deprivation. Comparisons of f-Hb distributions with those found in a pilot evaluation of FIT and three other countries were performed. Results f-Hb was documented for 887,248 screening participants, 422,385 men and 464,863 women. f-Hb varied by sex, age, deprivation quintile and geographical region. The f-Hb distributions by sex and age differed between the SBoSP and the pilot evaluation and the three other countries. Conclusions f-Hb is higher in men than in women and increases with age and deprivation in both sexes. f-Hb also varies by geographical region, independently of deprivation, and by country. The f-Hb distribution estimated by pilot evaluation may not represent the population distribution. Decision limits have advantages over reference intervals. Use of partitioned f-Hb thresholds for further investigation, based on the data generated, has advantages and disadvantages, as do risk scores based on a spectrum of influencing variables.

Transition to quantitative faecal immunochemical testing from guaiac faecal occult blood testing in a fully rolled-out population-based national bowel screening programme

ObjectiveFaecal immunochemical tests (FIT) are replacing guaiac faecal occult blood tests (FOBT) in colorectal cancer (CRC) screening. Data from the first year of FIT screening were compared with those from...

Randomized controlled trial: Flexible sigmoidoscopy as an adjunct to faecal occult blood testing in population screening.

Flexible sigmoidoscopy screening at around age 60 can reduce colorectal cancer incidence. Insufficient evidence exists on flexible sigmoidoscopy at age 60 in a population being offered biennial faecal occult blood test screening from age 50. This randomized controlled trial assessed if flexible sigmoidoscopy would be an effective adjunct to faecal occult blood test. In the Scottish Bowel Screening Programme between June 2014 and December 2015, 51,769 individuals were randomized to be offered flexible sigmoidoscopy instead of faecal occult blood test at age 60 or to continue faecal occult blood test. Those not accepting flexible sigmoidoscopy and those with normal flexible sigmoidoscopy were offered faecal occult blood test. All with flexible sigmoidoscopy-detected neoplasia or a positive faecal occult blood test result were offered colonoscopy. Overall flexible sigmoidoscopy uptake was 17.8%, higher in men than women, and decreased with increasing deprivation (25.7% in the least to 9.2% in the most deprived quintile). In those who underwent flexible sigmoidoscopy, detection rate for colorectal cancer was 0.13%, for adenoma 7.27%, and for total neoplasia 7.40%. In those who underwent colonoscopy after a positive flexible sigmoidoscopy, detection rate for colorectal cancer was 0.28%, adenoma 8.66%, and total neoplasia 8.83%. On an intention to screen basis, there was no difference in colorectal cancer detection rate between the study and control groups. Adenoma and total neoplasia detection rate were significantly higher in the study group, with odds ratios of 5.95 (95%CI: 4.69-7.56) and 5.10 (95%CI: 4.09-6.35), respectively. In a single screening round at age 60, there was low uptake and neoplasia detection rate. Flexible sigmoidoscopy detected significantly more neoplasia than faecal occult blood test alone.

Stable prevalence of faecal immunochemical test positivity over time in Italy.

The prevalence of guaiac faecal occult blood positivity among participants aged 50 in the Scottish Bowel Screening Programme showed a significant increase from 2007 to 2017. As a comparison, we examined the trend in the prevalence of faecal immunochemical test (FIT) positivity among participants aged 50 in the colorectal cancer screening programme of the Veneto region (north-east Italy) from 2006 to 2018. The target population includes residents aged 50-69, who are invited to repeat the FIT every two years. The screening programme uses the OC-Hemodia latex agglutination test, with a cut-off for positivity of 20 µg of haemoglobin per g of faeces. Based on 182,275 FITs performed on participants aged 50, overall FIT positivity was 3.6% in 2006 (95% confidence interval (CI): 3.1-4.2) and 3.7% (95% CI: 3.4-3.9) in 2018, showing no significant trend (p = 0.19). The prevalence of positive test results was higher in males throughout the study period. No gradient was seen for men (2006 = 4.4%, 95% CI: 3.6-5.3; 2018 = 4.2%, 95% CI: 3.9-4.6; p = 0.10) or women (2006 = 2.8%, 95% CI: 2.1-3.5; 2018 = 3.2%, 95% CI: 2.9-3.5; p = 0.84). In a FIT-based colorectal cancer screening programme in Italy, the test positivity over time was stable. Our findings suggest that the interpretation of faecal haemoglobin levels may not be geographically transferable.

Perceived colorectal cancer candidacy and the role of candidacy in colorectal cancer screening

Screening is a well-established tool to advance earlier cancer diagnosis. We used Davison’s concept of ‘candidacy’ to explore how individuals draw on collectively constructed images of ‘typical’ colorectal cancer (CRC) sufferers, or ‘candidates’, in order to evaluate their own risk and to ascertain the impact of candidacy on screening participation in CRC. We interviewed 61 individuals who were invited to participate in the Scottish Bowel Screening Programme. Of these, 37 were screeners (17 men and 20 women) and 24 non-screeners (13 men and 11 women). To analyse these data we used a coding frame that drew on: symptoms, risk factors, and retrospective and prospective candidacy. Few participants could identify a definite bowel cancer candidate and notions of candidacy were largely predicated on luck in the sense that anyone could be a candidate for CRC and there was little evidence to support a linear relationship between feelings of risk and screening decisions. Often participants described screening as part of a wider portfolio of being healthy and referred to feeling obliged to look after themselves. Our study suggests that rather than candidates for bowel cancer, screeners viewed themselves as candidates for screening by which screening decisions pointed towards the acceptance and normalisation of the rhetoric of personal responsibility for health. These findings have related theoretical and practical implications; the moral structure that underpins the new public health can be witnessed practically in the narratives by which those who see themselves as candidates for screening embrace wider positive health practices.

Changes in prevalence of faecal occult blood positivity over time.

Objectives Changes in the prevalence of faecal occult blood test positivity over time have not been previously reported, but could have important implications. This study examined the positivity of the initial guaiac faecal occult blood test, a surrogate marker for colorectal bleeding, in participants aged 50 in a national bowel screening programme. Methods Data from the Scottish Bowel Screening Programme were used to study the initial positivity of the guaiac faecal occult blood test between 2007 and 2017. Positive predictive values of the testing process for colorectal cancer and adenoma were assessed over the same time period. Results Across Scotland, the initial guaiac faecal occult blood test positivity increased from 4.1 to 10.8%. In NHS Grampian and NHS Fife, two of the three NHS Boards which began roll-out of screening in 2007, it increased from 4.0 to 10.9%. In the Scottish Bowel Screening Programme, the positive predictive value declined from 11.0 to 6.6% for colorectal cancer and increased from 31.6 to 39.8% for adenoma. Conclusions In the Scottish programme over a decade, initial guaiac faecal occult blood test positivity increased in participants aged 50. This may be associated with changes in lifestyle and might have implications for screening clinical outcomes, including positive predictive value.

Scottish Bowel Screening Programme colonoscopy quality - scope for improvement?

The delivery of the Scottish Bowel Screening Programme (SBoSP) is rooted in the provision of a high quality, effective and participant-centred service. Safe and effective colonoscopy forms an integral part of the process. Additional accreditation as part of a multi-faceted programme for participating colonoscopists, as in England, does not exist in Scotland. This study aimed to describe the quality of colonoscopy in the SBoSP and compare this to the English national screening standards. Data were collected from the SBoSP between 2007 and 2014. End-points for analysis were caecal intubation, cancer, polyp and adenoma detection, and complications. Overall results were compared with 2012 published English national standards for screening and outcomes from 2006 to 2009. During the study period 53 332 participants attended for colonoscopy. The colonoscopy completion rate was 95.6% overall. The mean cancer detection rate was 7.1%, the polyp detection rate was 45.7% and the adenoma detection rate was 35.5%. The overall complication rate was 0.47%. Colonoscopy quality in the SBoSP has exceeded the standard set for screening colonoscopy in England, despite not adopting a multi-faceted programme for screening colonoscopy. However, the overall adenoma detection rate in Scotland was 9.1% lower than that in England which has implications for colonoscopy quality and may have an impact on cancer prevention rates, a key aim of the SBoSP.

Uptake trends in the Scottish Bowel Screening Programme and the influences of age, sex, and deprivation.

Objective Age, sex, and deprivation are known factors influencing colorectal (bowel) cancer screening uptake. We investigated the influence of these factors on uptake over time. Methods Data from the Scottish Bowel Screening Programme (SBoSP) were collected between 2007 and 2014. End-points for analysis were uptake, faecal occult blood test positivity, and disease detection, adjusted for age, sex, deprivation, and year of screening. Results From 5,308,336 individual screening episodes documented, uptake gradually increased with increasing age up to 65-69 and was lower in men than women (52.4% vs. 58.7%, respectively). Deprivation had a significant effect on uptake by men and women of all age groups, with the most deprived least likely to complete a screening test. Uptake has increased with time in both sexes and across the deprivation gradient. The number needed to screen to detect significant neoplasia was significantly lower in men than women overall (170 vs. 365), and this held over all age and deprivation groups. The number needed to screen was also lower in the more deprived population. Conclusions Although lower age, male sex, and increased deprivation are associated with lower bowel cancer screening uptake in Scotland, uptake has increased since SBoSP introduction in all age groups, both sexes, and across the deprivation gradient. Despite a lower uptake, the number needed to screen to find significant disease was lower in men and in those with higher levels of deprivation.