Dr Robert Kerrison


Senior Lecturer and Co-Lead for Cancer Care
BSc, MSc, PhD

Academic and research departments

Cancer Care Expert Group, School of Health Sciences.

About

University roles and responsibilities

  • Cluster Co-Lead for Cancer Care
  • Module lead for Research Design and Methodology
  • Open Research Champion for School of Health Sciences
  • School of Health Sciences Athena Swan Committee Member

    My qualifications

    2018
    PhD in Psychology (IMPACT Studentship)
    University College London (UCL)
    2013
    MSc in Clinical Research (Distinction)
    University of Lincoln
    2011
    BSc in Applied Biomedical Science (1st Class)
    University of Surrey

    Previous roles

    2020 - 2021
    Senior Research Fellow
    University College London
    2018 - 2020
    Research Fellow
    University College London
    2012 - 2013
    Research Assistant
    Imperial College Healthcare NHS Trust

    Research

    Research interests

    Research projects

    Research collaborations

    Supervision

    Postgraduate research supervision

    Teaching

    Publications

    Robert S. Kerrison, Natalie Gil, Sandro Stoffel, Yasemin Hirst, Katriina Whitaker, Colin Rees, Stephen Duffy, Christian von Wagner (2024)Effectiveness of behaviour change techniques to address barriers to follow-up colonoscopy: results from an online survey and randomised factorial experiment, In: Annals of behavioral medicine Oxford University Press

    Background. Non-attendance at colonoscopy is associated with reduced colorectal cancer (CRC) survival.Purpose. The aim of this research was to quantify barriers to colonoscopy and test the effectiveness of behaviour change techniques (BCTs) to address them.Methods. Two studies were performed. In the first study, participants were asked to imagine their next CRC screening result was abnormal and were presented with the standard abnormal result letter used in the English CRC Screening Programme. Participants then completed a short survey. Multivariate regression tested associations between perceived barriers and intentions. In the second study, participants were randomly presented with a modified version of the abnormal results letter, which incorporated one or more BCTs, designed to target barriers identified in Study 1, using a 28 factorial design. Participants then completed the same survey used in Study 1. Multivariate regression tested the effectiveness of the BCTs to modify target barriers and intentions.Results. In Study 1, five items were associated with intentions, namely: ‘Lack of understanding that CRC can be asymptomatic’, ‘Perceived importance of screening’, ‘Transport/travel’, ‘Shared decision making and family influenced participation’ and ‘Fear of pain and discomfort’ (all p’s<0.05). In Study 2, the inclusion of a social support message, targeting ‘shared decision-making and family influenced participation’, facilitated independent decision making and increased intentions (both p’s<0.05). There was no evidence to support the remaining seven BCTs to modify barriers or intentions (all p’s <0.05). Conclusions. Inclusion of a social support message facilitated independent decision making and improved intentions.

    K. L. Whitaker, A. Cox, G. McErlean, A. Pal, K. Stansbury, M. Estupinan Fdez de Mesa, R. S. Kerrison, N. Gil, A. Marcu, Jo Armes, M. L. Yap, G. P. Delaney, C. Hoyo (2024)Integrating Implementation Theory to Address Inequities in Cancer Care: Perspectives from an International Working Group, In: European Journal of Cancer Care2024(1)9994508 Wiley

    Background . There are well-established, persistent inequities in cancer care and cancer outcomes within and between countries. The aim of this article is to explore how implementation theory, specifically the Consolidated Framework for Implementation Research (CFIR), alongside coproduction principles, could be used to maximise the effectiveness of innovations with a vision of reducing inequity in cancer care. Methods. Workshops were conducted with partners from US, Australia, and UK, participating in the University Global Partnership Network (UGPN), which funded the collaboration. From these workshops, three case studies were identified and the framework was applied to identify ways of using CFIR to maximise the effectiveness of innovations. Results. The three case studies focused on human papillomavirus (HPV) testing and vaccination, participation in clinical trials, and use of translation services. We identified opportunities, for each of the case studies, where CFIR could be applied to improve implementation and proposed recommendations to ensure effective implementation of innovations using CFIR domains, including individual constructs (e.g., awareness and cultural competence), inner setting constructs (e.g., technology infrastructure), and outer setting constructs (e.g., how services are monitored, evaluated, and commissioned). Conclusions. Applying CFIR as an implementation framework offers a structured and holistic approach to consider how to maximise the effectiveness of innovations in the context of reducing inequities in cancer care. Working with other countries to apply this framework also provides a uniform approach to understand and reduce inequities across a range of innovations and address the global mission to improve cancer care for all.

    Katriina Whitaker, Tetyana Perchyk, Robert S. Kerrison, Agnieszka Lemanska (2024)Challenges in understanding inequities in help-seeking for possible cancer symptoms, In: BMC global and public health249 Springer

    Tackling inequities in cancer outcomes is a global health priority. One avenue for improving early diagnosis of cancer is to ensure people know when and how to seek help for cancer symptoms and that this knowledge (and behaviour) is equitably distributed across the population. In this perspective piece we highlight the challenges in understanding sociodemographic differences in help-seeking behaviour (for example, how help-seeking is defined / conceptualised and subsequently assessed), as well as challenges with using existing datasets that are now more readily accessible than ever. Addressing these will strengthen methodological approaches to understand inequities in help-seeking and ways to tackle them.

    N Gil, A Cox, K L Whitaker, R S Kerrison (2024)Cancer risk-factor and symptom awareness among adults with intellectual disabilities, paid and unpaid carers, and healthcare practitioners: a scoping review, In: Journal of intellectual disability research68(3)193pp. 193-211

    The physical health of people with intellectual disabilities (ID) has been identified as an area of ongoing concern and priority. Research has increasingly focused on cancer, with studies indicating that people with ID are at an increased risk of cancer and of mortality, compared with the general population. This review aims to systematically identify and synthesise the published academic literature exploring cancer risk-factor and symptom awareness among people with IDs, carers and healthcare professionals. In line with Arksey and O'Malley's (2005) framework for scoping reviews, five incremental stages were followed: (1) identifying research question, (2) identifying relevant studies, (3) study selection, (4) extracting and charting of data, and (5) collating, summarising and reporting results. Findings were reported according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses extension for scoping reviews (PRISMA-Scr). The search strategy identified 352 records, 16 records met all eligibility criteria and were included for review. The studies address a range of areas including knowledge and awareness of cancer risk-factors and symptoms and interventions to promote awareness of cancer. Cancer risk-factor and symptom awareness is low among adults with ID, paid and unpaid carers and healthcare practitioners (HCPs). Theoretically underpinned, co-designed tools and interventions to improve awareness are lacking. There is uncertainty surrounding how to best support people with ID in raising cancer awareness, even within the professional healthcare environment. There is a predominance of research on breast cancer awareness. Future studies focusing on other cancers are needed to build a complete picture of awareness among adults with IDs, paid and unpaid carers, and HCPs.

    Sandro T Stoffel, Jing Hui Law, Robert Kerrison, Hannah R Brewer, James M Flanagan, Yasemin Hirst (2023)Testing behavioural messages to increase recruitment to health research when embedded within social media campaigns on Twitter: A Web-based Experiment (Preprint), In: JMIR formative research
    W. Atkin, A.J. Cross, I. Kralj-Hans, E. Macrae, C. Piggott, S. Pearson, K. Wooldrage, J. Brown, F. Lucas, A. Prendergast, N. Marchevsky, B. Patel, K. Pack, R. Howe, H. Skrobanski, N. Swart, J. Snowball, S.W. Duffy, S. Morris, C. von Wagner, S. Halloran, Robert Stephen Kerrison (2019)Faecal immunochemical tests versus colonoscopy for post-poly pectomy surveillance: An accuracy, acceptability and economic study, In: HEALTH TECHNOLOGY ASSESSMENT23(1)pp. I-84 NIHR JOURNALS LIBRARY

    Background In the UK, patients with one or two adenomas, of which at least one is ≥ 10 mm in size, or three or four small adenomas, are deemed to be at intermediate risk of colorectal cancer (CRC) and referred for surveillance colonoscopy 3 years post polypectomy. However, colonoscopy is costly, can cause discomfort and carries a small risk of complications. Objectives To determine whether or not annual faecal immunochemical tests (FITs) are effective, acceptable and cost saving compared with colonoscopy surveillance for detecting CRC and advanced adenomas (AAs). Design Diagnostic accuracy study with health psychology assessment and economic evaluation. Setting Participants were recruited from 30 January 2012 to 30 December 2013 within the Bowel Cancer Screening Programme in England. Participants Men and women, aged 60–72 years, deemed to be at intermediate risk of CRC following adenoma removal after a positive guaiac faecal occult blood test were invited to participate. Invitees who consented and returned an analysable FIT were included. Intervention We offered participants quantitative FITs at 1, 2 and 3 years post polypectomy. Participants testing positive with any FIT were referred for colonoscopy and not offered further FITs. Participants testing negative were offered colonoscopy at 3 years post polypectomy. Acceptibility of FIT was assessed using discussion groups, questionnaires and interviews. Main outcome measures The primary outcome was 3-year sensitivity of an annual FIT versus colonoscopy at 3 years for detecting advanced colorectal neoplasia (ACN) (CRC and/or AA). Secondary outcomes included participants’ surveillance preferences, and the incremental costs and cost-effectiveness of FIT versus colonoscopy surveillance. Results Of 8008 invitees, 5946 (74.3%) consented and returned a round 1 FIT. FIT uptake in rounds 2 and 3 was 97.2% and 96.9%, respectively. With a threshold of 40 µg of haemoglobin (Hb)/g faeces (hereafter referred to as µg/g), positivity was 5.8% in round 1, declining to 4.1% in round 3. Over three rounds, 69.2% (18/26) of participants with CRC, 34.3% (152/443) with AAs and 35.6% (165/463) with ACN tested positive at 40 µg/g. Sensitivity for CRC and AAs increased, whereas specificity decreased, with lower thresholds and multiple rounds. At 40 µg/g, sensitivity and specificity of the first FIT for CRC were 30.8% and 93.9%, respectively. The programme sensitivity and specificity of three rounds at 10 µg/g were 84.6% and 70.8%, respectively. Participants’ preferred surveillance strategy was 3-yearly colonoscopy plus annual FITs (57.9%), followed by annual FITs with colonoscopy in positive cases (31.5%). FIT with colonoscopy in positive cases was cheaper than 3-yearly colonoscopy (£2,633,382), varying from £485,236 (40 µg/g) to £956,602 (10 µg/g). Over 3 years, FIT surveillance could miss 291 AAs and eight CRCs using a threshold of 40 µg/g, or 189 AAs and four CRCs using a threshold of 10 µg/g. Conclusions Annual low-threshold FIT with colonoscopy in positive cases achieved high sensitivity for CRC and would be cost saving compared with 3-yearly colonoscopy. However, at higher thresholds, this strategy could miss 15–30% of CRCs and 40–70% of AAs. Most participants preferred annual FITs plus 3-yearly colonoscopy. Further research is needed to define a clear role for FITs in surveillance. Future work Evaluate the impact of ACN missed by FITs on quality-adjusted life-years.

    Robert Kerrison, Heema Shukla, Deborah Cunningham, Oyinlola Oyebode, Ellis Friedman (2013)Are text message reminders an effective intervention to improve uptake of breast screening? A randomised controlled trial, In: The Lancet (British edition)382(S3)pp. S9-S9 Elsevier Ltd

    Breast cancer is a major public health concern in the UK, one accounting for 16% of all cancer incidences and 7% of all cancer deaths. Fortunately, the natural history of this malignancy can be beneficially changed through the early detection and treatment of benign and malignant breast disease, which have been enabled by mammographic screening techniques. However, the success of screening programmes depends on their ability to attract the at-risk population, as well as the analytical specificity and sensitivity of the screening test itself. The NHS Breast Screening Programme attracts about three-quarters of the invited population each year. In 2010, all but one region reported a triennial coverage of more than 75%; London was the exception, reporting a regional coverage of 69%. London consistently fails to meet the national target. Missed appointments are a primary cause of inefficiency in health-care delivery, with adverse clinical implications for the non-attending patient and substantial monetary costs to the health service. To ensure the future success of the breast screening programme, development of strategies to improve uptake of hard-to-reach patients is imperative. Research has shown that receiving an appointment reminder by text message has been successful in reducing non-attendance in other areas of health care; the same might be true for breast screening. Our primary aim was to establish whether text message reminders can significantly improve the uptake of breast screening by women on an intention-to-treat basis in the London Borough of Hillingdon. Our secondary aim was to assess whether text message reminders are an effective intervention for improvement of uptake of breast screening by hard-to-reach patients such as women living in deprived areas and women of black and minority ethnic groups. We undertook a single-blind, randomised controlled trial to assess the effectiveness of sending a text message appointment reminder 48 h before a patient's first breast screening appointment to improve uptake of the programme by prevalent women aged 47–53 years in the London Borough of Hillingdon. 1640 women without a history of breast screening, implant, or bilateral mastectomy were included in the study and randomly assigned (1:1) to either the control (n=833) or intervention (n=807) group. Women in the control group were invited to screening but received no reminder for their appointment, whereas women in the intervention group received a text message reminder 48 h in advance. All women received an information letter about the study with their invitation from the West of London Breast Screening Service. Patients were not told whether they would be receiving a text message reminder or not. iPlato Patient Care Messaging was used to deliver text message reminders. This trial is registered with ClinicalTrials.gov, NCT01977599. Women in the text message reminder group were significantly more likely (odds ratio 1·32, 95% CI 1·12–1·53; p=0·0092) to attend their first breast screening appointment (69% uptake) than women in the control group (63% uptake). Of the 807 women assigned to the text message reminder group, only 316 (39%) had a valid mobile telephone number recorded on the GP Clinical System and were subsequently able to receive a text message reminder. Of the 316 patients who did receive a text message reminder, 252 (80%) attended breast screening. No adverse events were reported. These are preliminary data of an ongoing trial expected to be completed in September, 2013. Full results including deprivation and ethnic origin data will be available for the conference. Receipt of a text message reminder 48 h before a scheduled breast screening appointment significantly improves uptake. To ensure that the benefits of text message reminders are achieved, work is needed to improve patient mobile records. Research funded by Imperial College Healthcare Charity.

    Ellie McKay, Joy Wong, Stella Ward, Josephine Ruwende, Robert Kerrison (2024)Barriers and facilitators of abdominal aortic aneurysm screening in London: A cross-sectional survey, In: Journal of medical screening Sage

    Objectives: The aim of this research was to identify patient barriers and facilitators of abdominal aortic aneurysm (AAA) screening in London. Methods: A survey was distributed to 4211 adults, who had been invited for AAA screening in 2023. Barriers and facilitators were identified by comparing responses between attenders and non-attenders, using univariate logistic regression. Results: 271 surveys were returned. Attendance was higher among respondents with a body mass index (BMI) > 25 (odds ratio [OR]: 2.72, 95% CIs [1.15, 6.46]; p < 0.05) and those with one or more comorbidities (OR: 3.82, 95% CIs [1.63, 8.98]; p < 0.01), but lower among those who had not visited a healthcare appointment within the past 6 months (OR: 0.41, 95% CIs [0.18, 0.94]). Attendance was also lower among those who believe screening is only useful for people with symptoms (OR: 0.37; 95% CIs [0.16, 0.89]; p < 0.05), find it difficult to make time for medical appointments (OR: 0.25, 95% CIs [0.10, 0.60]; p < 0.01), find it difficult to get to medical appointments (OR: 0.40, 95% CIs [0.17, 0.91]; p < 0.05), have more important medical problems to worry about (OR: 0.28, 95% CIs [0.12, 0.64]; p < 0.01), cannot afford to travel to medical appointments (OR: 0.16, 95% CIs [0.07, 0.38]; p < 0.001), need help getting to appointments (OR: 0.33, 95% CIs [0.13, 0.86]; p < 0.05), have caring responsibilities (OR: 0.15, 95% CIs [0.06, 0.34]; p < 0.001), and forget about appointments (OR: 0.21, 95% CIs [0.09, 0.49]; p < 0.001). Conclusions: This study provides suggestive data on characteristics that might be associated with not attending AAA screening in London. The study design limitations mean that further work is required to evaluate these characteristics more reliably.

    Yasmin Hirst, Hanna Skrobanski, Lindsay C. Kobayashi, Nicholas Counsell, Natasha Djedovic, Josphine Ruwende, Mark Stewart, Christian Von Wagner, Robert Stephen Kerrison (2017)Text-message Reminders in Colorectal Cancer Screening (TRICCS): A randomised controlled trial, In: BRITISH JOURNAL OF CANCER116(11)pp. 1408-1414 NATURE PUBLISHING GROUP

    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.

    Sandro Stoffel, ROBERT STEPHEN KERRISON, Ivo Vlaev, C von Wagner (2020)Offering male endoscopists as decoy option to nudge disinclined women to have colorectal cancer screening, In: Journal of behavioral medicine43(3)pp. 511-518 Springer

    Previous studies have shown that a large proportion of women invited for bowel cancer screening prefer endoscopists of the same gender. We tested whether women who are initially disinclined to undergo flexible sigmoidoscopy screening would be more willing to have the test with a female practitioner if they were also offered a decoy appointment with a male practitioner. We conducted two online experiments with women aged 35-54, living in England, who did not intend to undergo flexible sigmoidoscopy screening. In both experiments, women were randomised to two conditions: (1) control (appointment with a female endoscopist) and (2) decoy (two appointments to choose from, one with a male endoscopist and one with a female endoscopist). Experiment 1 (N = 302) verified the conditions for the decoy using a conventional intention scale, while experiment 2 (N = 300) tested how the presence of the decoy influences the likelihood of women choosing the appointment with the female practitioner in a discrete choice task. While experiment 1 showed that the presence of the decoy increased intentions to attend the appointment with the female practitioner (p = 0.02), experiment 2 confirmed that women were more likely to choose the appointment with the female endoscopist if they were also offered the decoy (p 

    Sandro Stoffel, Mariella Bombagi, Robert S. Kerrison, Christian von Wagner , Benedikt Herrmann (2021)Testing Enhanced Active Choice to Optimize Acceptance and Participation in a Population-Based Colorectal Cancer Screening Program in Malta, In: Behavioral Medicine Taylor & Francis

    Opt-out strategies have been shown to improve participation in cancer screening; however, there are ethical concerns regarding the presumed consent. In this study, we tested an alternative opt-in strategy, called: "enhanced active choice," in which the response options summarize the consequences of the decision. The study was conducted as part of the Maltese colorectal cancer screening program, which offers men and women, aged 60-64, a "one-off" fecal immunochemical test (FIT). A total of 8349 individuals were randomly assigned to receive either an invitation letter that featured a standard opt-in strategy (control condition), or an alternative letter with a modified opt-in strategy (enhanced active choice condition). Our primary outcome was participation three months after the invitation was delivered. Additionally, we also compared the proportion who said they wanted to take part in screening. We used multivariable logistic regression for the analysis. Overall, 48.4% (N = 4042) accepted the invitation and 42.4% (N = 3542) did the screening test. While there were no statistically significant differences between the two conditions in terms of acceptance and participation, enhanced active choice did increase acceptance among men by 4.6 percentage points, which translated to a significant increase in participation of 3.4 percentage points. We conclude that enhanced active choice can improve male screening participation. Given the higher risk of CRC in men, as well as their lower participation screening, we believe this to be an important finding.

    Aradhna Kaushal, Y Hirst, Sara Tookey, Robert S. Kerrison, S Marshall, A Prentice, Daniel Vulkan, Stephen Duffy , Christian von Wagner (2020)Use of a GP-endorsed non-participant reminder letter to promote uptake of bowel scope screening: A randomised controlled trial in a hard-to-reach population, In: Preventive medicine141106268 Elsevier

    Previous research suggests that sending non-participants a reminder letter, 1 year after their initial invitation, can improve coverage for bowel scope screening (BSS), also known as flexible sigmoidoscopy screening. We hypothesised that adding a general practitioner's (GPs) endorsement to the reminder letter could improve coverage even further. We conducted a randomised controlled trial in North West London, UK. Participants were screening-eligible men and women who had not responded to their initial BSS invitation at least 12 months prior to the trial period. Eligible adults were randomised in a 1:1 ratio to receive either a GP-endorsed reminder letter, or a standard reminder letter from June to August 2019. Logistic regression models were used to test the effect of the GP endorsement on attendance at BSS, adjusting for sex, clinical commissioning group, and local area socioeconomic deprivation. In total, 1200 participants were enrolled into the study and randomised to either the control (n = 600) or the intervention (n = 600) group. Those who received the GP-endorsed reminder letter were only slightly more likely to attend BSS than those who received the standard reminder letter (4% vs. 3%); this difference was not statistically significant (Adjusted OR = 1.30; 95% CI: 0.69, 2.43). Adding a GP-endorsement to the annual reminder letter did not have an effect on attendance at BSS. One possible explanation for this is that the endorsement used was not personalised enough. Future research should examine stronger GP-endorsements or other methods to promote uptake.

    Yasemin Hirst, Hanna Skrobanski, Robert Kerrison, Lindsay C Kobayashi, Nicholas Counsell, Natasha Djedovic, Josephine Ruwende, Mark Stewart, Christian von Wagner (2016)Text-message reminders in colorectal cancer screening: a non-clinical randomised controlled trial, In: The Lancet (British edition)388pp. S55-S55 Elsevier Ltd

    In England, adults aged 60–74 years are eligible for colorectal cancer screening using a guaiac faecal occult blood test (gFOBt) kit. However, uptake of the gFOBt kit in London has been consistently below the national target. We investigated the effectiveness of a text-message reminder to improve uptake of the test kit in London. General practices in six Clinical Commissioning Groups (CCGs) in London were invited to take part in this randomised controlled trial. Between Jan 18 and March 14, 2016, screening-eligible adults were randomised (1:1, using a pseudorandom number generator) to the control group (gFOBT screening pathway in the English Bowel Cancer Screening Programme [usual care]) or intervention group (usual care plus a text-message reminder). Individuals in the intervention group who had not returned their screening kit were sent a reminder text-message on the eighth week of an 18 week gFOBt screening episode. The primary outcome was the total proportion of individuals returning the kit by 18 weeks, which was determined with intention-to-treat analysis. Ethics approval was given by the East Midlands National Research Ethics Service (15/EM/0159) and the Confidentiality Advisory Group (15/CAG/0156). This trial is registered with ISRCTN, number ISRCTN70904476. 141 (48%) of 295 general practices participated, and 8269 individuals were randomised (4135 usual care, 4134 intervention). Only 49% of individuals in both groups had registered a mobile number with their practice (n=4089). In the intervention group, 1393 individuals with a registered mobile had not returned their test kit within 8 weeks; reminder text-messages were successfully delivered to 1026 individuals (74%), of whom 189 (18%) subsequently took part in screening. Intention-to-treat analysis showed that uptake was 40% (1648 of 4135) in the control and 41% (1674 of 4134) in the intervention group (odds ratio 1·04, 95% CI 0·95–1·13; p=0·43). Pre-planned exploratory subgroup analyses showed no effect on uptake by sex, index of deprivation, age, or CCG. However, a 6 percentage point difference in uptake was seen among individuals receiving an invitation for the first time (control 35% [282/809] vs intervention 41% [297/733]) (odds ratio 1·31, 95% CI 1·00–1·71; p=0·03). Text-message reminders did not significantly increase the number of adequately screened individuals in London. Future research might however investigate the potential efficacy of text-messages among individuals invited for screening for the first time. London North West Healthcare NHS Trust.

    Sandro Stoffel, Stala Kioupi, Despina Ioannou, Robert S. Kerrison, Christian von Wagner , Benedikt Herrmann (2021)Testing messages from behavioral economics to improve participation in a population-based colorectal cancer screening program in Cyprus: Results from two randomized controlled trials, In: Preventive Medicine Reports24101499pp. 101499-101499 Elsevier

    Despite the benefits of colorectal cancer (CRC) screening, participation compares poorly to other screening programs. This study assessed the effectiveness of adding different behavioral economic-based messages, to the invitation letter, to increase uptake in the Cypriot CRC screening program. We performed two randomized controlled trials. In the first trial (‘Trial 1’), 3212 individuals, aged 50 to 69 years, were randomly allocated (1:1:1:1:1:1:1) to one of six intervention groups, or the control. The intervention groups received the standard invitation letter received by the control, with the addition of one of six messages based on the following behavioral economics principles: (1) social responsibility, (2) anticipated regret, (3) financial opportunity costs (of non-attendance), (4) benefit (of early detection), (5) scarcity effect (limited duration of the offer) and (6) social norms. The second trial (‘Trial 2’) tested the most efficacious message (social responsibility) against the control in a larger sample (N=3074). In both trials, the primary outcome was uptake eight weeks after the screening invitation. In trial 1, overall uptake was 20.6%. There were no significant differences between the control and the intervention conditions for the overall sample or men (all p’s>0.05). Highlighting the social consequences of cancer did, however, increase uptake rates among women (25.6% vs. 17.1%, aOR 1.67; 95% CI 1.05-2.66, p=0.031). We, therefore, tested this message in Trial 2. Uptake was similar to trial 1 with 20.7% (intervention: 20.8% vs control: 20.6%) and there was no impact on overall or uptake of men and women separately (all p’s>0.05).

    Dahir Sheik-Mohamud , Emily McBride , KATRIINA WHITAKER, Colin Rees, Stephen Duffy , Christian von Wagner , Robert Stephen Kerrison (2021)Patient barriers and facilitators of colonoscopy use: A rapid systematic review and thematic synthesis of the qualitative literature, In: Preventive Medicine106413

    Colonoscopy is the gold standard test in the diagnosis of colorectal cancer. Despite this, many people across the world decline the procedure when invited for screening, surveillance or diagnostic evaluation. The aim of this review was to characterise the barriers and facilitators of colonoscopy use described in the qualitative literature. We searched PubMed and PsychInfo for studies that explored barriers and facilitators of colonoscopy use. To determine the eligibility of studies, we first reviewed titles, then abstracts, and finally the full paper. We started with a narrow search, which we expanded successively, until the number of new publications eligible after abstract review was

    Robert S. Kerrison, Anna Robinson, Hanna Skrobanski, Ghalia Kayal, Aradhna Kaushal, Charlotte Ide-Walters, Adam Todd, Andrew Husband, Shivali Lakhani, Marsha Alter, Christian von Wagner, Lindsay MacDonald (2022)Demographic and psychological predictors of community pharmacists' cancer-related conversations with patients: a cross-sectional analysis and survey study, In: BMC health services research22(1)344 Springer Nature
    Robert Stephen Kerrison, Alex Jones, Jianhe Peng, Gabriele Price, Julia Verne, Elizabeth Alexandra Barley, Cam Lugton (2023)Inequalities in cancer screening participation between adults with and without severe mental illness: results from a cross-sectional analysis of primary care data on English Screening Programmes, In: British Journal of Cancer Springer Nature

    Background: People with severe mental illness (SMI) are 2.5 times more likely to die prematurely from cancer in England. Lower participation in screening may be a contributing factor. Methods: Clinical Practice Research Datalink data, for 1.71 million, 1.34 million and 2.50 million adults, were assessed (using multivariate logistic regression) for possible associations between SMI and participation in bowel, breast and cervical screening, respectively. Results: Screening participation was lower among adults with SMI, than without, for bowel (42.11% vs. 58.89%), breast (48.33% vs. 60.44%) and cervical screening (64.15% vs. 69.72%; all p

    Sandro Stoffel, Y Hirst, A Ghanouni, L McGregor, ROBERT STEPHEN KERRISON, Wouter Verstraete, A Gallagher, Jo Waller, Christian von Wagner (2019)Testing active choice for screening practitioner's gender in endoscopy among disinclined women: An online experiment, In: Journal of medical screening26(2)pp. 98-103

    A large proportion of women have a preference for a same-gender endoscopy practitioner. We tested how information about practitioner gender affected intention to have bowel scope screening in a sample of women disinclined to have the test. In an online experimental survey, women aged 35-54 living in England who did not intend to participate in bowel scope screening (N = 1060) were randomised to one of four experimental conditions: (1) control (practitioner's gender is unknown), (2) opposite-gender (male practitioner by default), (3) same gender (female practitioner by default), and (4) active choice (the patient could choose the gender of the practitioner). Intention was measured following the interventions. Of 1010 (95.3%) women who completed the survey, most were White-British (83.6%), and working (63.3%). Compared with control, both active choice and same-gender conditions increased intention among disinclined women (9.3% vs. 16.0% and 17.9%; OR: 1.85; 95% CI: 1.07-3.20 and OR: 2.07; 95% CI: 1.23-3.50). There were no differences in intention between the opposite-gender and control conditions (9.8% vs. 9.3%; OR: 1.06; 95% CI: 0.60-1.90) or the active choice and same-gender conditions (16.0% vs. 17.9%: OR: 0.89; 95% CI: 0.55-1.46, using same gender as baseline). Offering disinclined women a same-gender practitioner, either by choice or default, increased subsequent intention, while an opposite gender default did not negatively affect intention. Reducing uncertainty about gender of practitioner could positively affect uptake in women, and should be tested in a randomised controlled trial.

    Christian von Wagner , B Bonello, Sandro Stoffel, H. Skrobanski, R. Kerrison, L McGregor (2019)Predictors of intention translation in flexible sigmoidoscopy screening for colorectal cancer, In: Health Psychology38(12)pp. 1083-1095 American Psychological Association

    Objective: This prospective study aimed to identify predictors of intention and subsequent attendance of flexible sigmoidoscopy screening using constructs derived from the Health Belief Model (HBM). Method: A total of 4,330 people aged 54 years and registered at 1 of 83 participating English general practices were sent a preinvitation questionnaire to assess sociodemographics, HBM variables including perceived benefits, barriers, seriousness, health motivation, and external cues to action as well a range of other constructs and personal characteristics known to relate to cancer screening. Results: Of the 1,578 respondents (36.4%), 1,555 (98.5%) answered the intention question: 52.9% stated definitely yes, 38.1% probably yes, 6.8% probably not, and 2.2% definitely not. Intentions were positively associated with a higher score on a scale of benefits (odds ratio [OR] = 4.62; 95% confidence intervals [CI; 3.24, 6.59]) and health motivation, that is, interest in other ways of preventing colorectal cancer (OR = 2.61; 95% CI [1.62, 4.22]), while a higher score on perceived barriers (OR = 0.19; 95% CI [0.12, 0.31]) and currently following recommended healthy lifestyle behaviors (OR = 0.31; 95% CI [0.16, 0.59]) were negatively associated. Attendance was verified for 922 intenders (65.2%) of whom 737 (79.9%) attended. Attendance was predicted by health motivation (OR = 1.75; 95% CI [1.07, 2.86]), perceived benefits (OR = 1.82; 95% CI [1.37, 2.43]), perceived barriers (OR = 0.47; 95% CI [0.32, 0.69]), individual-level deprivation (OR = 0.26; 95% CI [0.14, 0.50]), and having diabetes (OR = 0.48; 95% CI [0.25, 0.94]). Conclusion: This study supported the usefulness of the HBM in predicting cancer screening and was further enhanced by adding non-HBM variables such as individual socioeconomic deprivation and comorbidities.

    Robert S. Kerrison, Elizabeth Travis, Christina Dobson, Katriina L. Whitaker, Colin Rees, Stephen Duffy , Christian von Wagner (2021)Barriers and facilitators to colonoscopy following fecal immunochemical test screening for colorectal cancer: A key informant interview study, In: Patient Education and Counseling Elsevier

    Objectives People who are referred for colonoscopy, following an abnormal colorectal cancer (CRC) screening result, are at increased risk of CRC. Despite this, many individuals decline the procedure. The aim of this study was to investigate why. Methods As little is currently known about non-attendance at follow-up colonoscopy, and follow-up of abnormal screening results is a nurse-led process, we decided to conduct key informant interviews with Specialist Screening Practitioners ([SSPs] nurses working in the English Bowel Cancer Screening Program). Interviews were conducted online. Transcripts were assessed using inductive and deductive coding techniques. Results 21 SSPs participated in an interview. Five main types of barriers and facilitators to colonoscopy were described, namely: Sociocultural, Practical, Psychological, Health-related and COVID-related. Key psychological and sociocultural factors included: ‘Fear of pain and discomfort associated with the procedure’ and ‘Lack of support from family and friends’. Key practical, health-related and COVID-related factors included: ‘Family and work commitments’, ‘Existing health conditions as competing priorities’ and ‘Fear of getting COVID-19 at the hospital'. Conclusions A range of barriers and facilitators to follow-up colonoscopy exist. Future studies conducted with patients are needed to further explore barriers to colonoscopy. Practice implications Strategies to reduce non-attendance should adopt a multifaceted approach.

    Natalie Maria Gil, Anna Clare Cox, Katriina Whitaker, Robert Stephen Kerrison (2023)Cancer risk-factor and symptom awareness among adults with intellectual disabilities, paid and unpaid carers, and healthcare practitioners. A scoping review., In: Journal of intellectual disability research Wiley

    Background: The physical health of people with intellectual disabilities has been identified as an area of ongoing concern and priority. Research has increasingly focused on cancer, with studies indicating people with intellectual disabilities are at an increased risk of cancer and of mortality, compared with the general population. This review aims to systematically identify and synthesize the published academic literature exploring cancer risk-factor and symptom awareness among people with intellectual disabilities, carers, and healthcare professionals. Methods: In line with Arksey and O’Malley’s (2005) framework for scoping reviews, five incremental stages were followed: (1) identify research question, (2) identifying relevant studies, (3) study selection, (4) extracting and charting of data, (5) collating, summarizing, and reporting results. Findings were reported according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses extension for scoping reviews, PRISMA-Scr. Results: The search strategy identified 352 records, 16 records met all eligibility criteria and were included for review. The studies address a range of areas including knowledge and awareness of cancer risk-factors and symptoms, and interventions to promote awareness of cancer. Conclusions: Cancer risk-factor and symptom awareness is low among adults with intellectual disabilities, paid and unpaid carers, and HCPs. Theoretically underpinned, co-designed tools and interventions to improve awareness are lacking. There is uncertainty surrounding how to best support people with intellectual disabilities in raising cancer awareness, even within the professional healthcare environment. There is a predominance of research on breast cancer awareness. Future studies focusing on other cancers is needed to build a complete picture of awareness among adults with intellectual disabilities, paid and unpaid carers, and HCPs.

    Ioanna Parisi, Angelica Vania Hosea, Sandro Stoffel, Martin Nemec, Sohail Badat, Edward Seward, Aradhna Kaushal, Robert Kerrison, Christian Von Wagner (2024)Evaluation of the safety, efficacy and feasibility of at-home capsule endoscopy, In: Frontline gastroenterology BMJ Publishing Group Ltd

    ObjectiveThe role of small bowel capsule endoscopy (SBCE) in diagnosing gastrointestinal diseases has long been established. Recently, colon CE (CCE) has been suggested as an alternative to colonoscopy. CE has been traditionally conducted at endoscopy units. However, during the COVID-19 pandemic, a switch was made to ‘at-home CE’ (ACE) which has continued to date. This study is an evaluation of ACE, focusing on safety, efficacy, feasibility and patient perceptions.MethodsThe study evaluated the performance of ACE in 105 consecutive patients, considering procedure outcomes, completion rates, complications and patient satisfaction. Self-report questionnaires were used to assess perceptions and preferences of 84 ACE patients and 43 in-hospital CE patients. ACE procedure involved preassessment calls, bowel preparation, equipment setup, virtual verbal consent, capsule ingestion, booster alerts and equipment collection. Descriptive statistics and tests of independence were used for data analysis.ResultsAll 105 ACE patients were able to have CE at home, with completion rates for SBCE, CCE and panenteric (Crohn’s) CE at 98.3%, 75.9% and 55.6%, respectively. Patients reported low levels of pain (94.1%), embarrassment (98.8%) and anxiety (82.1%). ACE saved time and money, as 42.9% of patients were able to avoid work absence and 52.4% avoided transportation costs. ACE patients reported high satisfaction with the overall procedure (mean=8.5, SD=1.9), and 83.3% would prefer CE again at home.ConclusionThis study demonstrates that at-home CEs are clinically effective and well received by patients, providing the opportunity to conduct the test in the comfort of patients’ homes.

    Christian von Wagner , Y Hirst, Sara Tookey, Robert S. Kerrison, S Marshall, A Prentice, Daniel Vulkan, U Macleod, Stephen Duffy (2018)Use of a GP-endorsed 12 months’ reminder letter to promote uptake of bowel scope screening: protocol for a randomised controlled trial in a hard-to-reach population, In: BMJ Open8(5)e022263

    Introduction Flexible sigmoidoscopy (FS) screening is associated with reduced colorectal cancer incidence and mortality when offered as a one-off test to men and women aged 55–64. The test, also referred to as the ‘bowel scope screening’ (BSS) test, was added to England’s national Bowel Cancer Screening Programme in March 2013, where it is offered to men and women aged 55. Since its implementation, uptake of the BSS test has been low, with only 43% of the eligible population attending an appointment. Sending non-participants a reminder at age 56 has been shown to improve uptake by up to nine percentage points at a single centre in London; we hypothesise that adding a general practitioners (GPs) endorsement to the reminder could improve uptake even further. Methods and analysis This paper describes the protocol for a randomised controlled trial which will examine the effectiveness of adding a GPs endorsement to a reminder for BSS non-participants aged 56. All screening-eligible adults who have not responded to a BSS appointment at London North West Healthcare NHS Trust within 12 months of their initial invitation will be randomised to receive either a GP-endorsed reminder letter or reminder letter without GP endorsement. The primary outcome will be the proportion of individuals screened within each group 8 weeks after the reminder. Statistical comparisons will be made using univariate and multivariate logistic regression, with ‘uptake’ as the outcome variable, GP reminder group as the exposure and sociodemographic variables as covariates. Ethics and dissemination The study was approved by the Yorkshire & Humber—Bradford Leeds Research Ethics Committee (16/YH/0298) and the Confidentiality Advisory Group (17/CAG/0162). The results will be disseminated in a peer-reviewed journal in accordance with the Consort statement and will be made available to the public.

    L McGregor, Robert S. Kerrison, TJ Green, U Macleod, Mark Hughes, Monica Gibbins, Stephen Morris, Colin Rees, Christian von Wagner (2018)Using primary care-based paper and telephone interventions to increase uptake of bowel scope screening in Yorkshire: a protocol of a randomised controlled trial, In: BMJ open8(7)e024616 BMJ Publishing Group

    Introduction: Evidence suggests bowel scope screening (BSS) can significantly reduce an individual’s risk of developing colorectal cancer (CRC). BSS for 55 year olds was therefore introduced to the English Bowel Cancer Screening Programme (BCSP) in 2013. However, the benefits are only gained from test completion and uptake is low (43%). Primary care involvement has consistently shown benefits to cancer screening uptake and so this study aims to build on this knowledge and evaluate general practitioner (GP) practice led interventions designed to increase BSS attendance. Methods and analysis: A three-arm randomised controlled trial will be conducted to evaluate three interventions: one intervention for prospective BSS invitees (primer letter with locally tailored leaflet sent by an individual’s GP practice) and two interventions for those who do not attend their BSS appointment (a self-referral letter sent by an individual’s GP practice and a patient navigation call made on behalf of an individual’s GP practice). The trial will be set in Yorkshire. Individuals soon to receive their invitation to attend BSS at one of the Hull and East Yorkshire Bowel Cancer Screening centre sites, will be randomly assigned to one of three groups: control (usual care; no input from GP practice), Intervention group A (primer letter/leaflet and a self-referral letter), Intervention group B (primer letter/leaflet and a patient navigation call). Attendance data will be obtained from the BCSP database (via National Health Service (NHS) Digital) 3 months after the last intervention. Regression analysis will compare uptake, and additional clinical outcomes, across the three groups. The analysis will be multivariate and adjust for several covariates including gender and area-level deprivation. Ethics and dissemination: NHS ethical approval has been obtained from London-Harrow Research Ethics Committee. The results will be submitted for publication in a peer-reviewed journal and presented at conferences.

    Objectives: In England, a significant proportion of people who take part in the national bowel cancer screening programme (BCSP) and have a positive faecal occult blood test (FOBt) result, do not attend follow-up colonoscopy (CC). The aim of this study was to investigate differences in intended participation in a follow-up investigation by diagnostic modality offered including CC, CT colonography (CTC) or capsule endoscopy (CE). Setting: We performed a randomised online experiment with individuals who had previously completed an FOBt as part of the English BCSP. Methods: Participants (n=953) were randomly allocated to receive one of three online vignettes asking participants to imagine they had received an abnormal FOBt result, and that they had been invited for a follow-up test. The follow-up test offered was either: CC (n=346), CTC (n=302) or CE (n=305). Participants were then asked how likely they were to have their allocated test or if they refused, either of the other tests. Respondents were also asked to cite possible emotional and practical barriers to follow up testing. Multivariable logistic regression models were used to investigate intentions. Results: Intention to have the test was higher in the CTC group (96.7%) compared with the CC group (91.8%; OR 2.64; 95% CI 1.22 to 5.73). CTC was considered less ‘off-putting’ (OR 0.66, 95% CI 0.47 to 0.94) and less uncomfortable compared with CC (OR 0.51, 95% CI 0.34 to 0.77). For those who did not intend to have the test they were offered, CE (39.7%) or no investigation (34.5%) was preferable to CC (8.6%) or CTC (17.2%). Conclusions: Alternative tests have the potential to increase attendance at diagnostic follow-up appointments.

    Robert S. Kerrison, A Prentice, S Marshall, S Choglay, Michael Levitan, Marsha Alter, A Ghanouni, L McGregor, Daniel Vulkan (2021)Ethnic inequalities in older adults bowel cancer awareness: findings from a community survey conducted in an ethnically diverse region in England, In: BMC Public Health21513 BMC

    To date, research exploring the public's awareness of bowel cancer has taken place with predominantly white populations. To enhance our understanding of how bowel cancer awareness varies between ethnic groups, and inform the development of targeted interventions, we conducted a questionnaire study across three ethnically diverse regions in Greater London, England. Data were collected using an adapted version of the bowel cancer awareness measure. Eligible adults were individuals, aged 60+ years, who were eligible for screening. Participants were recruited and surveyed, verbally, by staff working at 40 community pharmacies in Northwest London, the Harrow Somali association, and St. Mark's Bowel Cancer Screening Centre. Associations between risk factor, symptom and screening awareness scores and ethnicity were assessed using multivariate regression. 1013 adults, aged 60+ years, completed the questionnaire; half were of a Black, Asian or Minority ethnic group background (n = 507; 50.0%). Participants recognised a mean average of 4.27 of 9 symptoms and 3.99 of 10 risk factors. Symptom awareness was significantly lower among all ethnic minority groups (all p's 

    Christian von Wagner , Y Hirst, Jo Waller, A Ghanouni, L McGregor, ROBERT STEPHEN KERRISON, Wouter Verstraete, Ivo Vlaev, Monika Sieverding, Sandro Stoffel (2019)The impact of descriptive norms on motivation to participate in cancer screening – Evidence from online experiments, In: Patient education and counseling102(9)pp. 1621-1628 Elsevier B.V

    •Two online experiments testing descriptive social norms in cancer screening.•Increasing perceived uptake is positively associated with screening intention.•Providing feedback about normative beliefs does not affect perceived credibility of the uptake message.•The least credible messages stating highest uptake had largest effect on intentions. The current study tested in two online experiments whether manipulating normative beliefs about cancer screening uptake increases intention to attend colorectal screening among previously disinclined individuals. 2461 men and women from an Internet panel (Experiment 1 N = 1032; Experiment 2, N = 1423) who initially stated that they did not intend to take up screening were asked to guess how many men and women they believe to get screened for colorectal cancer. Across participants, we varied the presence/absence of feedback on the participant’s estimate, as well as the stated proportion of men and women doing the screening test. Across the two experiments, we found that receiving one of the experimental messages stating that uptake is higher than estimated significantly increased the proportion of disinclined men and women becoming intenders. While, we found a positive relationship between the communicated uptake and screening intentions, we did not find evidence that providing feedback on the estimate has an added benefit. Screening intention can be effectively manipulated through a high uptake message. Communication of high screening uptake is an easy and effective way to motivate disinclined individuals to engage in colorectal cancer screening.

    Ghalia Kayal, Robert Stephen Kerrison, Yasemin Hirst, Christian von Wagner (2023)Patients experience of using colonoscopy as a diagnostic test after a positive FOBT/FIT: a systematic review of the quantitative literature, In: BMJ Open13(9)e071391 BMJ Publishing Group

    Objectives: Faecal occult blood testing (FOBT) and faecal immunochemical testing (FIT) are among the most used screening modalities for colorectal cancer (CRC). Colonoscopy is also widely used as a screening and diagnostic test for adults with a positive FOBT/FIT. Patient experience of colonoscopy is an important component for most CRC screening programmes. Individuals with negative experiences are less likely to engage with colonoscopy in the future and can deter others from attending colonoscopy when invited. This review synthesised data on patient experience with colonoscopy, following a positive result, to provide insights into how to improve patient experience within the English Bowel Cancer Screening Programme. Methods: MEDLINE, EMBASE and PsycINFO were searched for quantitative questionnaire studies evaluating patient-reported experience with colonoscopy, following a positive screening FOB/FIT result. The search was limited to studies published between 2000 and 2021 (ie, when the first FOBT/FIT screening programmes for CRC were introduced). Data-driven and narrative summary techniques were used to summarise the literature. Results: In total, six studies from the UK (n=4), Spain (n=1) and the Netherlands (n=1) were included in the review (total participants: 152 329; response rate: 68.0–79.3%). Patient experiences were categorised into three ‘stages’: ‘pre-colonoscopy’, ‘during the test’ and ‘post-colonoscopy’. Overall, patients reported a positive experience in all six studies. Bowel preparation was the most frequently endorsed issue experienced pre-test (experienced by 10.0–41.0% of individuals, across all studies), pain and discomfort for during the test (experienced by 10.0–21.0% of participants) and abdominal pain and discomfort after the test (these were experienced by 14.8–22% of patients). Conclusion: This review highlighted that patient-reported experiences associated with colonoscopy were generally positive. To improve the colonoscopy experience, bowel screening centres should investigate means to: make bowel preparation more acceptable, make colonoscopy less painful and reduce post-colonoscopy symptoms.

    Sandro T. Stoffel, Jing Hui Law, Robert Kerrison, Hannah R. Brewer, James M. Flanagan, Yasemin Hirst (2022)Testing the Effectiveness of an Animated Decision Aid to Improve Recruitment of Control Participants in a Case-Control Study: Web-Based Experiment, In: Journal of Medical Internet Research24(8)e40015 JMIR Publications

    Background: Participation in case-control studies is crucial in epidemiological research. The self-sampling bias, low response rate, and poor recruitment of population representative controls are often reported as limitations of case-control studies with limited strategies to improve participation. With greater use of web-based methods in health research, there is a further need to understand the effectiveness of different tools to enhance informed decision-making and willingness to take part in research. Objective: This study tests whether the inclusion of an animated decision aid in the recruitment page of a study website can increase participants’ intentions to volunteer as controls. Methods: A total of 1425 women were included in a web-based experiment and randomized to one of two experimental conditions: one in which they were exposed to a simulated website that included the animation (animation; n=693, 48.6%), and one in which they were exposed to the simulated website without the animation (control; n=732, 51.4%). The simulated website was adapted from a real website for a case-control study, which invites people to consider taking part in a study that investigates differences in purchasing behaviors between women with and without ovarian cancer and share their loyalty card data collected through 2 high street retailers with the researchers. After exposure to the experimental manipulation, participants were asked to state (1) their intention to take part in the case-control study, (2) whether they would be willing to share their loyalty card for research, and (3) their willingness to be redirected to the real website after completing the survey. Data were assessed using ordinal and binary logistic regression, reported in percentages (%), adjusted odds ratio (AOR), and 95% confidence intervals. Results: Including the animation in the simulated website did not increase intentions to participate in the study (AOR 1.09; 95% CI 0.88-1.35) or willingness to visit the real study website after the survey (control 50.5% vs animation 52.6%, AOR 1.08; 95% CI 0.85-1.37). The animation, however, increased the participants’ intentions to share the data from their loyalty cards for research in general (control 17.9% vs animation 26%; AOR 1.64; 95% CI 1.23-2.18). Conclusions: While the results of this study indicate that the animated decision aid did not lead to greater intention to take part in our web-based case-control study, they show that they can be effective in increasing people’s willingness to share sensitive data for health research.

    Christian Von Wagner, Bernadette Bonello, Sandro Stoffel, Hanna Skrobanski, Madeleine Freeman, Lesley M. McGregor, Robert Stephen Kerrison (2018)Barriers to bowel scope (flexible sigmoidoscopy) screening: A comparison of non-responders, active decliners and non-attenders 11 Medical and Health Sciences 1117 Public Health and Health Services, In: BMC Public Health18(1) Biomed Central

    Background Participation in bowel scope screening (BSS) is low (43%), limiting its potential to reduce colorectal cancer (CRC) incidence and mortality. This study aimed to quantify the prevalence of barriers to BSS and examine the extent to which these barriers differed according to non-participant profiles: non-responders to the BSS invitation, active decliners of the invitation, and non-attenders of confirmed appointments. Methods Individuals invited for BSS between March 2013 and December 2015, across 28 General Practices in England, were sent a questionnaire. Questions measured initial interest in BSS, engagement with the information booklet, BSS participation, and, where applicable, reasons for BSS non-attendance. Chi-square tests of independence were performed to examine the relationship between barriers, non-participant groups and socio-demographic variables. Results 1478 (45.8%) questionnaires were returned for analysis: 1230 (83.2%) attended screening, 114 (7.7%) were non-responders to the BSS invitation, 100 (6.8%) were active decliners, and 34 (2.3%) were non-attenders. Non-responders were less likely to have read the whole information booklet than active decliners (x2 (2, N = 157) = 7.00, p = 0.008) and non-attenders (x2 (2, N = 101) = 8.07, p = 0.005). Non-responders also had lower initial interest in having BSS than either active decliners (x2 (2, N = 213) = 6.07, p = 0.014) or non-attenders (x2 (2, N = 146) = 32.93, p 

    L McGregor, B Bonello, ROBERT STEPHEN KERRISON, C Nickerson, G Baio, Lindy Berkman, Colin Rees, WS Atkin, J Wardle, Christian von Wagner (2016)Uptake of Bowel Scope (Flexible Sigmoidoscopy) Screening in the English National Programme: the first 14 months, In: Journal of medical screening23(2)pp. 77-82 Sage

    To examine uptake in the first six pilot centres of the English Bowel Scope Screening (BSS) programme, which began in early 2013 and invites adults aged 55 for a one off Flexible Sigmoidoscopy. Between March 2013 and May 2014 the six pilot centres sent 21,187 invitations. Using multivariate logistic regression analysis, we examined variation in uptake by gender, socioeconomic deprivation (using the Index of Multiple Deprivation), area-based ethnic diversity (proportion of non-white residents), screening centre, and appointment time (routine: daytime vs out-of-hours: evening/weekend). Uptake was 43.1%. Men were more likely to attend than women (45% vs 42%; OR 1.136, 95% CI 1.076, 1.199, p 

    ROBERT STEPHEN KERRISON, L McGregor, N Counsell, S Marshall, A Prentice, John Isitt, Colin Rees, Christian von Wagner (2018)Use of Two Self-referral Reminders and a Theory-Based Leaflet to Increase the Uptake of Flexible Sigmoidoscopy in the English Bowel Scope Screening Program: Results From a Randomized Controlled Trial in London, In: Annals of behavioral medicine52(11)pp. 941-951 Oxford University Press

    Reminder letters, which prompt ‘no-shows’ to self-refer for bowel cancer screening, increase uptake and thereby the total number of pre-cancerous lesions detected.

    Elizabeth Travis, ROBERT STEPHEN KERRISON, Daryl B O'Connor, Laura Ashley (2022)Barriers and facilitators to colonoscopy for cancer detection: patient and practitioner perspectives, In: Psychology & health Routledge

    Objective: To further understand the barriers and facilitators to attending colonoscopy examination following a positive routinely offered stool test result, from the perspective of patients and Specialist Screening Practitioners (SSPs).Methods: Qualitative semi-structured interviews were conducted. Participants (N= 32) were patients (n = 20) who, as part of the Bowel Cancer Screening Programme (BCSP) in England, were invited to attend a colonoscopy examination, and SSPs (n= 12), who worked for the BCSP in England. Framework analysis included inductive and deductive coding.Results: Anxiety was as a key barrier cited by patients and SSPs, arising from the moment the patient received the invitation letter. Notably, procedural-related anxieties centred upon the fear of pain and discomfort and test invasiveness. The role of family, friends and the SSP were recognised by patients and SSPs to facilitate participation. Many patients, yet not SSPs, emphasised an obligation to attend all medical test invitations.Conclusion: Practically-orientated strategies suggested by patients and SSPs address the patient barriers identified. These include earlier information to patients on the option of sedation for pain relief, earlier notification of potential financial support for patients unable to fund their own travel costs, and fewer uses of the term cancer within written materials.

    Robert S. Kerrison, Christian von Wagner , A Ghanouni, TJ Green, U Macleod, Mark Hughes, Colin Rees, Stephen Duffy , L McGregor (2020)Lessons Learned From Conducting a Rapid Review: A Case Study Examining Factors Associated With Flexible Sigmoidoscopy Screening Use, In: SAGE Research Methods Cases: Medicine and Health SAGE

    Rapid reviews enable researchers to obtain a snapshot of what is known about a topic in a quick and systematic way, and are increasingly becoming an important aspect of the research literature. Despite this, there are currently no formal guidelines as to how best to conduct a rapid review. One method is to begin with a narrow search, and to expand the search successively, until the number of new/additional publications considered potentially eligible, based on title and abstract alone, is less than 1% of the total number of publications found overall (at this point, one can be reasonably confident that expanding the search is unlikely to yield any considerable new information). One of the main advantages of this method is that it provides a rationale for terminating the search at a given point, thereby making it less time-consuming than many other methods, which require the reviewer(s) to screen all articles found in response to a comprehensive list of search terms. In this case study, we describe our experience using the aforementioned method to review the literature investigating factors associated with flexible sigmoidoscopy (“bowel scope”) screening use, and the lessons learned from it. We also describe the problems encountered in performing our review, and the steps implemented to overcome them. Finally, we provide suggestions for methodological improvements for the benefit of those considering conducting a rapid review in the future.

    ROBERT STEPHEN KERRISON, H Shukla, DA Cunningham, O Oyebode, E Friedman (2015)Text-message reminders increase uptake of routine breast screening appointments: a randomised controlled trial in a hard-to-reach population, In: British journal of cancer112(6)pp. 1005-1010 Springer Nature

    There is a need for interventions to promote uptake of breast screening throughout Europe. We performed a single-blind randomised controlled trial to test whether text-message reminders were effective. Two thousand two hundred and forty women receiving their first breast screening invitation were included in the study and randomly assigned in a 1 : 1 ratio to receive either a normal invitation only (n=1118) or a normal invitation plus a text-message reminder 48 h before their appointment (n=1122). In the intention-to-treat analysis, uptake of breast screening was 59.1% among women in the normal invitation group and 64.4% in the text-message reminder group (χ(2)=6.47, odds ratio (OR): 1.26, 95% confidence intervals (CI): 1.05-1.48, P=0.01). Of the 1122 women assigned to the text-message reminder group, only 456 (41%) had a mobile number recorded by their GP and were thereby sent a text. In the per-protocol analysis, uptake by those in the control group who had a mobile number recorded on the GP system was 59.77% and by those in the intervention group who were sent a reminder 71.7% (χ(2)=14.12, OR=1.71, 95% CI=1.29-2.26, P

    Thomas Duffy, Natalie Maria Gil, Benzeer Siddique, Stephen Duffy, Andrew Prentice, Sarah Marshall, N. Djedovic, Michael Lewis, Josephine Ruwende, Christian von Wagner, Robert Stephen Kerrison (2024)Comparing the effectiveness and cost-effectiveness of text-message reminders and telephone patient navigation to improve the uptake of faecal immunochemical test screening among non-responders in London: a randomised controlled trial protocol, In: BMJ open14(6)079482 BMJ Publishing Group

    Introduction : Participation in bowel cancer screening is lower in regions where there is high ethnicdiversity and / or socioeconomic deprivation. Interventions, such as text message reminders andpatient navigation (PN), have the potential to increase participation in these areas. As such, there isinterest in the comparative effectiveness of these interventions to increase bowel cancer screeningparticipation, as well as their relative cost-effectiveness.Methods and Analysis: This study will use a three-arm randomised controlled trial design tocompare the effectiveness and cost-effectiveness of text message reminders and PN to increase theuptake of bowel cancer screening in London. Participants will be individuals who have not returned acompleted faecal immunochemical test (FIT) kit within 13 weeks of receiving a routine invitation fromthe London bowel cancer screening hub. Participants will be randomised (in a 1:1:1 ratio) to receiveeither: (1) usual care (i.e. 'no intervention’), (2) a text message reminder at 13 weeks, followed byrepeated text message reminders at 15, 17 and 19 weeks (in the event of non-response); or, (3) a textmessage reminder at 13 weeks, followed by PN telephone calls at 15, 17 and 19 weeks in the eventof non-response. The primary endpoint will be participation in bowel cancer screening, defined as ‘thereturn of a completed kit by week 24’. Statistical analysis will use multivariate logistic regression, andwill incorporate pairwise comparisons of all three groups, adjusted for multiple testing.Ethics and Dissemination: Approvals to conduct the research have been obtained from UniversityCollege London’s Joint Research Office (Ref: 150666), the Screening Research, Innovation andDevelopment Advisory Committee (‘RIDAC’, Ref: 2223 014 BCSP Kerrison), the Health ResearchAuthority (Ref: 22/WM/0212) and the Confidentiality Advisory Group (Ref: 22/CAG/0140). Results willbe conveyed to stakeholders, notably those managing the screening programme, and published inpeer-reviewed journals / presented at academic conferences.Trial registration: This trial is registered with the International Standardised Randomised ControlledTrials Number Registry (ISRCTN).

    Y Hirst, Robert Kerrison, Lindsay C. Kobayashi, N Counsell, Natasha Djedovic, Josephine Ruwende, M Stewart, Christian von Wagner (2016)Text Reminders in Colorectal Cancer Screening (TRICCS): Protocol for a randomised controlled trial, In: BMC Public Health1674 BMC

    Screening with the guaiac faecal occult blood test (gFOBt) is associated with improved colorectal cancer (CRC) survival, and is offered biennially to men and women aged 60-74 years in England's national Bowel Cancer Screening Programme (BCSP). Uptake of the gFOBt is low, with only 54 % of the eligible population completing the test. Text-message reminders could improve uptake of gFOBt. This paper describes the protocol for a randomised controlled trial, which will examine the effectiveness of a text-message reminder to promote uptake of gFOBt screening in the BCSP. Individual mobile telephone data from 180 general practices in London with existing mobile-health services will be linked to the national BCSP information system via a secure on-line network. All screening-eligible adults registered with a participating practice will be randomised, to receive either usual care (N = 1600) or usual care plus a text-message reminder to self-complete and return their kit eight weeks after their initial invitation (N = 1600). The primary outcome will be the proportion of individuals who return an adequately completed gFOBt kit within 18 weeks of the initial invitation. Differences in uptake between groups will be evaluated using a logistic regression analysis, adjusting for individual-level and area-level socio-demographic variables. This will be the first large-scale randomised trial of a text-message reminder in a national screening programme for CRC. If effective, this study provides a cost-effective means to promote uptake of CRC screening in an organised programme. Current Controlled Trials ISRCTN70904476 (18/09/2015).

    Sarah Huf, Robert S. Kerrison, Dominic King, Tim Chadborn, Adele Richmond, DA Cunningham, E Friedman, H Shukla, Fu-Min Tseng, Gaby Judah, A Darzi, Ivo Vlaev (2020)Behavioral economics informed message content in text message reminders to improve cervical screening participation: Two pragmatic randomized controlled trials, In: Preventive Medicine139106170 Elsevier

    The objective of the reported research was to assess the impact of text message (SMS) reminders and their content on cervical screening rates. Women invited for cervical screening in Northwest London from February–October 2015 were eligible. 3133 women aged 24–29 (Study 1) were randomized (1, 1) to ‘no SMS’ (control), or a primary care physician (PCP) endorsed SMS (SMS-PCP). 11,405 women aged 30–64 (Study 2), were randomized (1, 1:1:1:1:1:1) to either: no SMS, an SMS without manipulation (SMS), the SMS-PCP, an SMS with a total or proportionate social norm (SMS-SNT or SMS-SNP), or an SMS with a gain-framed or loss-framed message (SMS-GF and SMS-LF). The primary outcome was participation at 18 weeks. In Study 1 participation was significantly higher in the SMS-PCP arm (31.4%) compared to control (26.4%, aOR, 1.29, 95%CI: 1.09–1·51; p = 0.002). In Study 2 participation was highest in the SMS-PCP (38.4%) and SMS (38.1%) arms compared to control (34.4%), (aOR: 1.19, 95%CI: 1.03–1.38; p = 0.02 and aOR: 1.18, 95%CI: 1.02–1.37; p = 0.03, respectively). The results demonstrate that behavioral SMSs improve cervical screening participation. The message content plays an important role in the impact of SMS. The results from this trial have already been used to designing effective policy for cervical cancer screening. The NHS Cervical Screening Programme started running a London-wide screening SMS campaign which was based on the cervical screening trial described here. According to figures published by Public Health England, after six months attendance increased by 4.8%, which is the equivalent of 13,400 more women being screened at 18 weeks.

    Robert S. Kerrison, Christian von Wagner , TJ Green, Monica Gibbins, U Macleod, Mark Hughes, Colin Rees, Stephen Duffy , L McGregor (2019)Rapid review of factors associated with flexible sigmoidoscopy screening use, In: Preventive medicine120pp. 8-18 Elsevier

    Flexible sigmoidoscopy (FS) screening has been shown to reduce colorectal cancer (CRC) incidence and mortality among screened adults. The aim of this review was to identify patient-related factors associated with the screening test's use. We searched PubMed for studies that examined the association between FS screening use and one or more factors. To determine the eligibility of studies, we first reviewed titles, then abstracts, and finally the full paper. We started with a narrow search, which we expanded successively (by adding ‘OR’ terms) until the number of new publications eligible after abstract review was

    R. S. Kerrison, A Prentice, S Marshall, S Choglay, Sandro Stoffel, Colin Rees, C von Wagner (2021)Implementation of long-term non-participant reminders for flexible sigmoidoscopy screening, In: Preventive Medicine Reports21101308 Elsevier

    The clinical effectiveness of screening is highly dependent on uptake. Previous randomised controlled trials suggest that non-participant reminders, which highlight the opportunity to re-book an appointment, can improve participation. The present analysis examines the impact of implementing these reminders within the English Flexible Sigmoidoscopy (FS) Screening Programme, which offers once-only FS screening to adults aged 55–59 years. We assessed the screening status of 26,339 individuals invited for once-only FS screening in England. A total of 10,952 (41.6%) had attended screening, and were subsequently ineligible. The remaining 15,387 had not attended screening, and were selected to receive a reminder, 1–2 years after their invitation. Descriptive statistics were used to assess the increase in uptake and the adenoma detection rate (ADR) of those who self-referred, six months after the delivery of the final reminder. Pearson’s Chi-Square was used to compare the ADR between those who attended when invited and those who self-referred. Of the 15,387 adults eligible to receive a reminder, 13,626 (88.6%) were sent a reminder as intended (1,761 were not sent a reminder, due to endoscopy capacity). Of these, 8.0% (n = 1,086) booked and attended an appointment, which equated to a 4.1% increase in uptake from 41.6% at baseline, to 45.7% at follow-up. The ADR was significantly higher for those who self-referred, compared with those who attended when invited (13.3% and 9.5%, respectively; X2 = 16.138, p = 0.000059). The implementation of non-participant reminders led to a moderate increase in uptake. Implementing non-participant reminders could help mitigate the negative effects of COVID-19 on uptake.

    ROBERT STEPHEN KERRISON, L McGregor, S Marshall, John Isitt, N Counsell, Colin Rees, Christian von Wagner (2017)Improving uptake of flexible sigmoidoscopy screening: a randomized trial of nonparticipant reminders in the English Screening Programme, In: Endoscopy49(1)pp. 35-43 Georg Thieme Verlag KG

    Abstract Background and study aims  Uptake of flexible sigmoidoscopy screening in the English Bowel Scope Screening (BSS) Programme is low. The aim of this study was to test the impact of a nonparticipant reminder and theory-based leaflet to promote uptake among former nonresponders (previously did not confirm their appointment) and nonattenders (previously confirmed their appointment but did not attend). Patients and methods  Eligible adults were men and women in London who had not attended a BSS appointment within 12 months of their invitation. Individuals were randomized (1:1:1) to receive no reminder (control), a 12-month reminder plus standard information booklet (TMR-SIB), or a 12-month reminder plus bespoke theory-based leaflet (TMR-TBL) designed to address barriers to screening. The primary outcome of the study was the proportion of individuals screened within each group 12 weeks after the delivery of the reminder. Results  A total of 1383 men and women were randomized and analyzed as allocated (n = 461 per trial arm). Uptake was 0.2 % (n = 1), 10.4 % (n = 48), and 15.2 % (n = 70) in the control, TMR-SIB, and TMR-TBL groups, respectively. Individuals in the TMR-SIB and TMR-TBL groups were significantly more likely to attend screening than individuals in the control group (adjusted odds ratio [OR] 53.7, 95 % confidence interval [CI] 7.4 – 391.4, P  

    ROBERT STEPHEN KERRISON, L McGregor, S Marshall, John Isitt, N Counsell, J Wardle, Christian von Wagner (2016)Use of a 12 months' self-referral reminder to facilitate uptake of bowel scope (flexible sigmoidoscopy) screening in previous non-responders: a London-based feasibility study, In: British journal of cancer114(7)pp. 751-758 British Journal of Cancer

    In March 2013, NHS England extended its national Bowel Cancer Screening Programme to include 'one-off' Flexible Sigmoidoscopy screening (NHS Bowel Scope Screening, BSS) for men and women aged 55. With less than one in two people currently taking up the screening test offer, there is a strong public health mandate to develop system-friendly interventions to increase uptake while the programme is rolling out. This study aimed to assess the feasibility of sending a reminder to previous BSS non-responders, 12 months after the initial invitation, with consideration for its potential impact on uptake. This study was conducted in the ethnically diverse London Boroughs of Brent and Harrow, where uptake is below the national average. Between September and November 2014, 160 previous non-responders were randomly selected to receive a reminder of the opportunity to self-refer 12 months after their initial invitation. The reminder included instructions on how to book an appointment, and provided options for the time and day of the appointment and the gender of the endoscopist performing the test. To address barriers to screening, the reminder was sent with a brief locally tailored information leaflet designed specifically for this study. Participants not responding within 4 weeks were sent a follow-up reminder, after which there was no further intervention. Self-referral rates were measured 8 weeks after the delivery of the follow-up reminder and accepted as final. Of the 155 participants who received the 12 months' reminder (returned to sender, n=5), 30 (19.4%) self-referred for an appointment, of which 24 (15.5%) attended and were successfully screened. Attendance rates differed by gender, with significantly more women attending an appointment than men (20.7% vs 8.8%, respectively; OR=2.73, 95% CI=1.02-7.35, P=0.05), but not by area (Brent vs Harrow) or area-level deprivation. Of the 30 people who self-referred for an appointment, 27 (90%) indicated a preference for a same-sex practitioner, whereas three (10%) gave no preference. Preference for a same-sex practitioner was higher among women than men (χ(2)=7.78, P

    Natalie Gil, Anna Cox, Katriina L Whitaker, Robert Kerrison (2022)Inequity in HPV vaccination, primary HPV screening, and sexual health education for people with learning disabilities, autism, and severe mental illness: A discussion, In: RqR Enfermería Comunitaria10(4)pp. 3-7
    Emily McBride , Hiromi Mase, Robert S. Kerrison, Laura A.V. Marlow, Jo Waller (2021)Improving Postal Survey Response Using Behavioural Science: A Nested Randomised Control Trial, In: BMC Medical Research Methodology21(280) BMC

    Background Systematic reviews have identified effective strategies for increasing postal response rates to questionnaires; however, most studies have isolated single techniques, testing the effect of each one individually. Despite providing insight into explanatory mechanisms, this approach lacks ecological validity, given that multiple techniques are often combined in routine practice. Methods We used a two-armed parallel randomised controlled trial (n = 2702), nested within a cross-sectional health survey study, to evaluate whether using a pragmatic combination of behavioural science and evidenced-based techniques (e.g., personalisation, social norms messaging) in a study invitation letter increased response to the survey, when compared with a standard invitation letter. Participants and outcome assessors were blinded to group assignment. We tested this in a sample of women testing positive for human papillomavirus (HPV) at cervical cancer screening in England. Results Overall, 646 participants responded to the survey (response rate [RR] = 23.9%). Logistic regression revealed higher odds of response in the intervention arm (n = 357/1353, RR = 26.4%) compared with the control arm (n = 289/1349, RR = 21.4%), while adjusting for age, deprivation, clinical site, and clinical test result (aOR = 1.30, 95% CI: 1.09–1.55). Conclusion Applying easy-to-implement behavioural science and evidence-based methods to routine invitation letters improved postal response to a health-related survey, whilst adjusting for demographic characteristics. Our findings provide support for the pragmatic adoption of combined techniques in routine research to increase response to postal surveys.

    Natalie Gil, Helen Su, Kirandeep Kaur, Michael Barnett, Anna Murray, Stephen Duffy, Christian von Wagner, Rob Kerrison (2022)Patient experience and satisfaction with symptomatic faecal immunochemical testing: An explanatory sequential mixed-methods evaluation, In: British Journal of General Practice Royal College of General Practitioners

    Background: Recent evidence suggests that faecal immunochemical testing (FIT) can rule out colorectal cancer in symptomatic adults. To date, there is little research exploring experiences of FIT for this population. Aim: To explore patient experience and satisfaction with FIT in an ‘early adopter’ site in England. Design: We used an explanatory sequential mixed-methods approach combining mailed quantitative surveys with semi-structured telephone interviews. Methods: Multivariate logistic regression was used to analyse quantitative data. Thematic analysis was used to assess qualitative transcripts. Results: The survey had 260 respondents and found satisfaction with FIT was high (88.7%). Compared with test satisfaction, the proportion of respondents satisfied with GP consultation, and how they received their results, was lower (74.4% and 76.2%, respectively). Multivariate analysis showed increased area-level deprivation and not receiving an explanation of the purpose of the test were associated with lower satisfaction with GP consultation (both P-values

    Robert S. Kerrison, Natalie Gil, Elizabeth Travis, Robyn Jones, Katriina L. Whitaker, Colin Rees, Stephen Duffy, Christian von Wagner (2023)Barriers to colonoscopy in UK colorectal cancer screening programmes: Qualitative interviews with ethnic minority groups, In: Psycho-Oncology Wiley

    Objective People from ethnic minority backgrounds are less likely to attend colonoscopy, following faecal immunochemical test screening, and are more likely to be diagnosed with colorectal cancer at an advanced stage as a result. The aim of this research was to explore the barriers and facilitators to attending colonoscopy, perceived by ethnic minority groups living in the United Kingdom. Methods Semi-structured online and telephone interviews were conducted with thirty men and women of Black-African (n = 5), Black-Caribbean (n = 5), South Asian (n = 10) and White British (n = 10) descent. Participants were eligible for screening, but had not necessarily been invited for colonoscopy. All interviews were conducted in the participant's first language and were assessed using Framework-analysis, in line with a conceptual framework developed from previous interviews with healthcare professionals. Results Five thematic groups of barriers and facilitators were developed: ‘Locus of control’, ‘Cultural attitudes and beliefs’, ‘Individual beliefs, knowledge and personal experiences with colonoscopy and cancer’, ‘Reliance on family and friends’ and ‘Health concerns’. Differences were observed, between ethnic groups, for: ‘Locus of control’, ‘Cultural attitudes and beliefs’ and ‘Reliance on family and friends’. Black and South Asian participants frequently described the decision to attend colonoscopy as lying with ‘God’ (Muslims, specifically), ‘the doctor’, or ‘family’ (Locus of control). Black and South Asian participants also reported relying on friends and family for ‘language, transport and emotional support’ (Reliance on family and friends). Black-African participants, specifically, described cancer as ‘socially taboo’ (Cultural attitudes and beliefs). Conclusions The results highlight several targets for culturally-tailored interventions to make colonoscopy more equitable.

    Robert Stephen Kerrison, Andrew Prentice, Sarah Marshall, Christian von Wagner (2022)Why are most colorectal cancers diagnosed outside of screening? A retrospective analysis of data from the English bowel screening programme, In: Journal of Medical Screening SAGE Publications

    Objective Despite several interventions to increase participation in England, most colorectal cancers (CRCs) are diagnosed outside of the screening programme. The aims of this study were to better understand why most CRCs are diagnosed externally, the extent to which this is due to suboptimal uptake of screening, and the extent to which it is due to other factors, such as false-negative test results. Setting / Methods We performed a clinical audit of 1011 patients diagnosed with CRC at St Mark's Hospital (Harrow, UK) between January 2017 and December 2020. Data on the diagnostic pathway and screening history of individuals were extracted from the bowel cancer screening system and assessed using descriptive statistics. Results 446/1011 (44.1%) patients diagnosed with CRC were eligible for screening at the time of diagnosis. Of these, only 115/446 (25.8%) were diagnosed through screening. Among those diagnosed via non-screening pathways, 210/331 (63.4%) had never taken part in screening, 31/331 (9.4%) had taken part but were not up to date, and 89/331 (26.9%) had taken part and were up-to-date (of these, 82/89 [92.2%] had received a normal or weak positive test result, and 5/89 [5.6%] had received a positive result and declined colonoscopy). Conclusion Nearly two-thirds of screening eligible patients diagnosed through a non-screening pathway had never taken part in screening. This represents the single largest source of inefficiency within the screening programme, followed by missed findings and inconsistent participation. Given the improved outcomes associated with screen-detected cancers, there is a strong public health mandate to encourage participation.