The English Bowel (colorectal cancer, CRC) Screening Programme involves sending a guaiac Faecal Occult Blood test (gFOBt) to the homes of men and women aged 60–74 every two years. It is now widely accepted that gFOBt screening reduces cancer-specific mortality [
Recently, there has been interest in the extent to which socioeconomic inequalities are modified or maintained by the information sent with invitation materials. Health communication is often didactic (factsheets, charts, etc.), targeting a more “rational” thinking process. However, this presentation may contradict preexisting beliefs and behaviours and subsequently elicit defensive processing, such as counterarguing or disengagement, allowing the individual to preserve their positive self-image, while undermining the effectiveness of the health message [
Narrative information is thought to target a more “heuristic/affective” thinking process and, therefore, may be considered a less direct confrontation of a person’s health beliefs, thereby reducing initial defensive processing [
In a recent qualitative study exploring people’s responses to narrative information about colorectal cancer screening information, respondents described narrative information as helpful, making the information more vivid, relevant, and subsequently reassuring [
We developed a narrative leaflet, containing quotes and stories of the CRC screening experience from previous participants, as part of a wider project to test four separate, theoretically driven interventions to reduce socioeconomic inequalities in CRC screening uptake [
In the initial evaluation of the leaflet, we conducted a questionnaire study with over 1200 individuals approaching the age of screening and observed that adding the narrative leaflet to standard screening information enhanced intention to screen, particularly by strengthening anticipated peace of mind from screening, enhancing feelings of vulnerability to colorectal cancer without screening, reducing perceived disgust with the screening procedure, and strengthening the belief that screening can reduce the chance of dying from the disease [
A two-arm cluster randomised controlled trial (
In England, the CRC screening programme invites men and women who are registered with a GP to complete a gFOBt every two years from the age of 60 (up to 74 years). The programme is coordinated through 5 hubs (Midlands and North West, Southern, London, North East, and Eastern), where each mails screening invitations to approximately 60,000 eligible people per month (prevalent and incident screening rounds combined; “prevalent” relates to individuals who are being invited for the first time or have not accepted previous invitations to take part in the CRC screening programme and “incident” relates to individuals who have participated in screening at least once before). The invitation letter is mailed with an information booklet (“Bowel Cancer Screening: the Facts”; online version is available at
Organisation and schedule of the national trial.
Completing the gFOBt involves taking two small samples from three separate bowel motions over a 10-day period. The CRC screening programme in England does not impose any dietary restrictions for completion of the test [
A reminder letter is sent if a completed kit is not returned within 4 weeks. If there is no return within a further 13 weeks, the “screening episode” is closed for that round of screening. The next round of the screening invitation process starts again 2 years later (up to the age of 74).
This study was integrated into the usual running of each hub over a 10-day period (March 4–15, 2013). For two hubs, the printing and distribution of invitation material is conducted in-house through a system operated by Health and Social Care Information Centre (HSCIC). For the remaining three hubs, this activity is contracted out to REAL Digital International, Croydon, UK (RDI). Both CfH and RDI agreed to accommodate the inclusion of an additional leaflet as per study design.
As per the CRC screening programme protocol, each person was mailed an NHS envelope containing a one-page invitation letter and “The Facts” booklet. Approximately one week later they were mailed a gFOBt kit with a standard instructions leaflet. If no response was received within 4 weeks, a standard reminder letter was sent.
The initial NHS envelope contained, in addition to the invitation letter and “The Facts” booklet, an additional narrative leaflet (see Supplementary Appendix
The randomisation schedule was provided to CfH, RDI, and each corresponding hub in advance of the study commencing. Each schedule was derived from a random number generator, whereby 10 numbers corresponding to the 10-day study period were generated. Days assigned numbers 1–5 and 6–10 were designated either control (SI) or intervention days (SI + N).
The hubs, CfH, and RDI could not be blind to group allocation, but a lack of direct contact with participants meant that any associated bias was minimised. Participants were unaware of their involvement in a randomised study and therefore blind to group allocation (unless they communicated with an eligible person assigned to the other group during this study).
The Index of Multiple Deprivation (IMD) scores of each address was the basis for estimating deprivation. IMD assesses deprivation at the small area level (i.e., lower layer superoutput areas (LSOA) covering about 1500 people) and takes into account seven deprivation domains: income, employment, health and disability, education, skills and training barriers to housing and services, crime, and living environment. Each domain is scored separately and they are combined to produce an IMD score for each LSOA. Postcodes are linked to LSOAs and therefore to IMD scores. IMD scores have been shown to be correlated with individual markers of SES [
The effect of screening round was investigated with individuals classified as either prevalent first time invitees, prevalent previous nonresponders, or incident episodes (participated at least once previously). Age, gender, and hub were additionally considered potential moderators. An additional outcome was the time taken to return a completed gFOBt kit.
The target sample size was based on achieving a reduction in the SES gradient associated with screening uptake. We assumed a fixed proportional effect in each hub and estimated an average increase of 3 percentage points, based on increasing uptake by 5 percentage points in the lowest (fifth) IMD quintile (most socially disadvantaged group) and 1 percentage point in the highest (first) quintile, giving an overall 1-2-3-4-5 percentage point difference by quintile using the method of Brentnall and colleagues [
The final calculation assumed the composition of the hub that required the largest sample (North West) to ensure a sufficiently large number of people. Because the study randomised by day and there is variation in the number of invitations sent per day, an inflation factor of 1.7 was included. With 90% power and 5% statistical significance, 46,000 individuals (23,000 per arm) were required to detect a 1-2-3-4-5 percentage point difference in uptake in the least to most deprived IMD quintile, respectively. Due to the volume of invitations sent out by each hub during a working week (70,000–80,000), this sample would have been achieved within only 5 days, but such small number of clusters would have a high risk of bias. The intervention therefore ran for 10 days, providing a sample of approximately 140,000–160,000, to achieve enough clusters to avoid bias [
The primary outcome was analysed by logistic regression in a univariable model and then a multivariable model adjusting for age, gender, hub and screening round.
HSCIC organised for the relevant pseudoanonymised data to be extracted from the Bowel Cancer Screening System and transferred to one coordinating hub (Southern). At this hub, the data were cleaned and further anonymised before being securely transferred to the research team for analysis.
An audit of current and imminent bowel cancer screening research and health promotion activities within England was carried out and regularly updated throughout the course of this research study. This audit served to highlight any possible confounding factors to consider in our analysis and involved regular contact with key informants including Quality Assurance Reference Centre (QARC) directors, Specialist Screening Practitioners (SSPs), BCSP managers, and representatives from the National Awareness and Early Diagnosis Initiative (NAEDI), Cancer Research Network, and Strategic Clinical Network.
Between March 4 and 15, 2013, 150,417 individuals were allocated to either the control group (SI: 76,695) or the intervention group (SI + N: 73,722) (see Figure
Baseline characteristics.
SI | SI + N | |
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Median (range) | Median (range) | |
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Age at invitation (in years) | 65.0 (59.0–74.0) | 65.0 (59.0–74.0) |
IMD deprivation score | 15.1 (0.5–87.8) | 15.1 (0.5–87.8) |
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% ( |
% ( |
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Gender | ||
Female | 51.0 (39,086) | 51.5 (37,937) |
Male | 49.0 (37,609) | 48.5 (35,785) |
IMD quintile | ||
1st quintile (0–8.49, least deprived) | 22.3 (17,073) | 23.2 (17,027) |
2nd quintile (8.50–13.79) | 23.1 (17,675) | 22.5 (16,517) |
3rd quintile (13.80–21.35) | 21.1 (16,161) | 20.8 (15,287) |
4th quintile (21.36–34.17) | 17.5 (13,385) | 17.6 (12,897) |
5th quintile (34.18–87.80, most deprived) | 15.9 (12,127) | 16.0 (11,722) |
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|
|
Hub | ||
Midlands and North West | 27.5 (21,118) | 29.1 (21,421) |
Southern | 21.8 (16,723) | 28.0 (20,667) |
London | 11.5 (8,795) | 11.5 (8,509) |
North East | 16.8 (12,900) | 17.7 (13,053) |
Eastern | 22.4 (17,159) | 13.7 (10,072) |
Screening round | ||
Prevalent first time invitees | 16.3 (12,510) | 20.7 (15,281) |
Prevalent previous nonresponders | 29.8 (22,892) | 30.1 (22,209) |
Incident episodes | 53.8 (41,293) | 49.1 (36,232) |
SI: standard information; SI + N: standard information plus narrative leaflet; IMD: index of multiple deprivation.
Flowchart of participation.
The median time (range) to return a kit was 26 days (10–126) and 26 days (11–126) for the SI and SI + N groups, respectively. Spoilt kits were returned by only 1,204 individuals (SI: 595; SI + N: 609). Overall, more than half (57.7%; 86,726) of those invited returned a gFOBt kit within 18 weeks of their invitation that led to a “definitive” screening test result of either “normal” or “abnormal” within the timeframe of the study (i.e., were “adequately screened”).
The intervention arm (SI + N = 56.7%; 41,822) had a proportion of adequately screened individuals 1.8 percentage points lower than the control arm (SI = 58.5%; 44,904); this reduction was not statistically significant (unadjusted odds ratio (OR) = 0.93, 95% confidence interval (CI) 0.81–1.06,
For each trial arm, the proportion of adequately screened individuals within each IMD quintile decreased as the level of deprivation increased (SI: 66.8% to 46.0%; SI + N: 64.6% to 42.4%; Table
Proportion of individuals invited who were adequately screened†, according to gender, age, IMD quintile‡, hub, and screening round.
SI | SI + N | Adjusted odds ratio |
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|
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% ( |
% ( |
(95% CI) | ||
Total | 58.5 (44,904) | 56.7 (41,822) | 1.00 (0.96–1.03) | 0.80 |
Gender | ||||
Female | 60.9 (23,811) | 59.3 (22,499) | 1.01 (0.96–1.05) | 0.77 |
Male | 56.1 (21,093) | 54.0 (19,323) | 0.98 (0.94–1.03) | 0.50 |
Age (median split) | ||||
<65 years | 55.2 (19,014) | 53.3 (18,264) | 1.01 (0.97–1.05) | 0.67 |
≥65 years | 61.2 (25,890) | 59.7 (23,558) | 0.98 (0.92–1.04) | 0.45 |
IMD quintile | ||||
1st quintile (0–8.49, least deprived) | 66.8 (11,411) | 64.6 (11,005) | 0.98 (0.93–1.04) | 0.57 |
2nd quintile (8.50–13.79) | 62.7 (11,080) | 62.1 (10,253) | 1.00 (0.94–1.06) | 0.91 |
3rd quintile (13.80–21.35) | 59.4 (9,601) | 58.3 (8,911) | 1.05 (0.97–1.13) | 0.24 |
4th quintile (21.36–34.17) | 52.9 (7,083) | 50.7 (6,535) | 1.00 (0.94–1.06) | 0.95 |
5th quintile (34.18–87.80, most deprived) | 46.0 (5,580) | 42.4 (4,966) | 0.92 (0.86–0.98) | 0.02 |
Hub | ||||
Midlands and North West | 57.6 (12,163) | 53.4 (11,439) | 0.95 (0.88–1.03) | 0.22 |
Southern | 60.2 (10,069) | 61.5 (12,712) | 1.00 (0.91–1.10) | 0.98 |
London | 49.2 (4,327) | 45.4 (3,864) | 1.00 (0.95–1.05) | 0.95 |
North East | 60.8 (7,837) | 59.1 (7,716) | 0.98 (0.90–1.06) | 0.56 |
Eastern | 61.2 (10,508) | 60.5 (6,091) | 1.07 (0.99–1.16) | 0.08 |
Screening round | ||||
Prevalent first time invitees | 49.8 (6,231) | 50.2 (7,678) | 1.03 (0.99–1.08) | 0.14 |
Prevalent previous nonresponders | 14.3 (3,284) | 14.0 (3,113) | 0.97 (0.90–1.04) | 0.35 |
Incident episodes | 85.7 (35,389) | 85.6 (31,031) | 0.99 (0.94–1.04) | 0.64 |
SI: standard information; SI + N: standard information plus narrative leaflet
†Returned a gFOBt kit (or kits) within 18 weeks of being sent the invitation, with a definitive “normal” (no further investigation required) or “abnormal” (requiring referral for further investigation, usually colonoscopy) screening test result available at the time of data extraction.
‡546 (274 SI and 272 SI + N) individuals missing an IMD score, 301 of these were adequately screened (149 SI and 152 SI + N).
There was no difference in the overall proportion of individuals adequately screened between the trial groups by age at invitation (median age = 65 yrs; Table
Proportion of individuals who were adequately screened†, according to IMD quintile‡ and median age at invitation.
Age at invitation <65 years | Age at invitation ≥65 years | |||
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SI | SI + N | SI | SI + N | |
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% ( |
% ( |
% ( |
% ( |
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Adequately screened | 55.2 (19,014) | 53.3 (18,264) | 61.2 (25,890) | 59.7 (23,558) |
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1st quintile (least deprived) | 64.4 (4,801) | 61.4 (4,639) | 68.7 (6,610) | 67.2 (6,366) |
2nd quintile | 59.3 (4,577) | 59.6 (4,424) | 65.3 (6,503) | 64.1 (5,829) |
3rd quintile | 55.6 (4,045) | 55.1 (3,907) | 62.5 (5,556) | 61.0 (5,004) |
4th quintile | 49.4 (3,043) | 47.1 (2,955) | 55.9 (4,040) | 54.1 (3,580) |
5th quintile (most deprived) | 43.5 (2,471) | 39.3 (2,267) | 48.3 (3,109) | 45.4 (2,699) |
SI: standard information; SI + N: standard information plus narrative leaflet.
†Returned a gFOBt kit (or kits) within 18 weeks of being sent the invitation, with a definitive “normal” (no further investigation required) or “abnormal” (requiring referral for further investigation, usually colonoscopy) screening test result available at the time of data extraction.
‡546 (274 SI and 272 SI + N) individuals missing an IMD score, 301 of these were adequately screened (149 SI and 152 SI + N).
There was no difference in the overall proportion adequately screened between the trial arms by gender (Table
Proportion of individuals who were adequately screened†, according to IMD quintile‡ and gender.
Males | Females | |||
---|---|---|---|---|
SI | SI + N | SI | SI + N | |
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% ( |
% ( |
% ( |
% ( |
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Adequately screened | 56.1 (21,093) | 54.0 (19,323) | 60.9 (23,811) | 59.3 (22,499) |
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1st quintile (least deprived) | 63.9 (5,342) | 61.2 (5,014) | 69.7 (6,069) | 67.8 (5,991) |
2nd quintile | 59.8 (5,186) | 59.6 (4,757) | 65.5 (5,894) | 64.4 (5,496) |
3rd quintile | 56.7 (4,460) | 55.6 (4,055) | 61.9 (5,141) | 60.7 (4,856) |
4th quintile | 50.8 (3,353) | 48.1 (3,029) | 55.0 (3,730) | 53.1 (3,506) |
5th quintile (most deprived) | 44.7 (2,676) | 40.7 (2,394) | 47.3 (2,904) | 44.1 (2,572) |
SI: standard information; SI + N: standard information plus narrative leaflet.
†Returned a gFOBt kit (or kits) within 18 weeks of being sent the invitation, with a definitive “normal” (no further investigation required) or “abnormal” (requiring referral for further investigation, usually colonoscopy) screening test result available at the time of data extraction.
‡546 (274 SI and 272 SI + N) individuals missing an IMD score, 301 of these were adequately screened (149 SI and 152 SI + N).
The proportion adequately screened was lower in people who had not previously taken part in CRC screening and decreased with deprivation in both arms (Table
Proportion of individuals who were adequately screened†, according to IMD quintile‡ and screening round.
Prevalent first time invitees | Prevalent previous nonresponders | Incident episodes | ||||
---|---|---|---|---|---|---|
SI | SI + N | SI | SI + N | SI | SI + N | |
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% ( |
% ( |
% ( |
% ( |
% ( |
% ( |
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Adequately screened | 49.8 (6,231) | 50.2 (7,678) | 14.3 (3,284) | 14.0 (3,113) | 85.7 (35,389) | 85.6 (31,031) |
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1st quintile (least deprived) | 58.0 (1,585) | 58.9 (1,953) | 17.8 (705) | 16.3 (685) | 87.9 (9,121) | 88.0 (8,367) |
2nd quintile | 54.5 (1,494) | 55.9 (1,827) | 16.1 (775) | 16.3 (705) | 87.2 (8,811) | 86.7 (7,721) |
3rd quintile | 50.5 (1,312) | 51.4 (1,601) | 14.2 (665) | 15.7 (709) | 85.7 (7,624) | 86.1 (6,601) |
4th quintile | 44.7 (1,011) | 44.4 (1,282) | 13.1 (598) | 12.5 (552) | 83.7 (5,474) | 84.1 (4,701) |
5th quintile (most deprived) | 37.9 (801) | 37.3 (979) | 11.1 (527) | 9.6 (448) | 81.0 (4,252) | 79.8 (3,539) |
SI: standard information; SI + N: standard information plus narrative leaflet.
†Returned a gFOBt kit (or kits) within 18 weeks of being sent the invitation, with a definitive “normal” (no further investigation required) or “abnormal” (requiring referral for further investigation, usually colonoscopy) screening test result available at the time of data extraction.
‡546 (274 SI and 272 SI + N) individuals missing an IMD score, 301 of these were adequately screened (149 SI and 152 SI + N).
There was no difference in the overall proportion of individuals adequately screened between the trial groups in each hub (Table
Proportion of individuals who were adequately screened†, according to IMD quintile‡ and hub.
Midlands and North West | Southern | London | North East | Eastern | ||||||
---|---|---|---|---|---|---|---|---|---|---|
SI | SI + N | SI | SI + N | SI | SI + N | SI | SI + N | SI | SI + N | |
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% ( |
% ( |
% ( |
% ( |
% ( |
% ( |
% ( |
% ( |
% ( |
% ( |
|
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||||||||||
Adequately screened | 57.6 (12,163) | 53.4 (11,439) | 60.2 (10,069) | 61.5 (12,712) | 49.2 (4,327) | 45.4 (3,864) | 60.8 (7,837) | 59.1 (7,716) | 61.2 (10,508) | 60.5 (6,091) |
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1st quintile (least deprived) | 66.9 (2,628) | 62.2 (2,409) | 65.1 (3,345) | 65.4 (4,523) | 63.9 (683) | 56.1 (573) | 69.1 (1,471) | 68.8 (1,476) | 68.3 (3,284) | 65.8 (2,024) |
2nd quintile | 62.8 (2,859) | 60.4 (2,674) | 62.3 (2,666) | 63.8 (3,287) | 55.3 (839) | 51.6 (778) | 66.8 (1,841) | 65.7 (1,822) | 62.8 (2,875) | 63.7 (1,692) |
3rd quintile | 60.3 (2,528) | 56.3 (2,370) | 58.9 (2,330) | 61.2 (2,843) | 50.8 (907) | 49.2 (908) | 63.7 (1,579) | 62.9 (1,591) | 60.1 (2,257) | 58.2 (1,199) |
4th quintile | 53.3 (1,926) | 49.1 (1,832) | 53.0 (1,222) | 52.7 (1,431) | 44.6 (1,068) | 41.7 (1,020) | 58.0 (1,455) | 56.6 (1,440) | 55.1 (1,412) | 55.8 (812) |
5th quintile (most deprived) | 45.9 (2,195) | 41.5 (2,119) | 47.4 (448) | 49.8 (568) | 40.7 (815) | 34.5 (572) | 49.1 (1,474) | 45.2 (1,368) | 46.3 (648) | 43.0 (339) |
SI: standard information; SI + N: standard information plus narrative leaflet.
†Returned a gFOBt kit (or kits) within 18 weeks of being sent the invitation, with a definitive “normal” (no further investigation required) or “abnormal” (requiring referral for further investigation, usually colonoscopy) screening test result available at the time of data extraction.
‡546 (274 SI and 272 SI + N) individuals missing an IMD score, 301 of these were adequately screened (149 SI and 152 SI + N).
As part of the concurrent initiative survey, we received details of 62 local health promotion activities and 17 research projects being undertaken at the same time as this trial. None of these initiatives were limited to occurring on the same days the narrative leaflet was sent out.
This study assessed the impact of the addition of a narrative-based leaflet to existing information on inequalities in uptake of CRC screening in England. The leaflet was designed to reduce barriers to uptake but it neither increased the overall number of people returning a completed gFOBt kit nor decreased the associated SES gradient. In fact, this study appeared to produce negative results at various points. However, we found that this was due to the imbalance in screening round, with a higher proportion of incident screens in the control group; this is because ~85% of incident screens were adequately screened, compared to only ~50% of prevalent first-time invitees and ~14% of prevalent previous nonresponders. After adjusting for baseline characteristics, we found no evidence of an overall effect in either direction (OR = 1.00, 95% CI 0.96–1.03,
Our study benefited from a pragmatic design, including access to a very large sample size, with no exclusion criteria, and the real-life applicability of the intervention within an established CRC screening programme [
Firstly, it meant that the additional information leaflet could only be inserted at the preinvitation stage; due to logistics of the packing equipment used in two hubs, inclusion of the leaflet with the second mail out (test kit and instructions) was not possible. Although research indicates the importance of a preinvitation contact point at improving uptake [
Secondly, the narrative leaflet had to be added to, rather than replace, existing informational literature. Despite the brevity of the narrative leaflet, by adding it to existing information material, the total amount of written material received by the individual increased. This might have undermined the goal of making the screening offer more visible to lower-literacy individuals. The impact of a “stand-alone” narrative leaflet at different points in the invitation pathway and in comparison to existing materials therefore needs to be examined.
In addition, the provision of narrative information in different formats (e.g., web, video) which integrate oral and nonverbal communication methods, thus allowing more narrative information to be communicated, and perhaps in a more engaging manner, should also be tested. Previous research has also suggested a benefit of using either a targeted or tailored approach in health communication materials (e.g., [
Further limitations of the study include the marker of SES used to depict the gradient. While the Index of Multiple Deprivation (IMD) is a comprehensive measure of area deprivation, it does not include personal circumstances and therefore individuals may not be as affluent or as disadvantaged as their postcode suggests.
The current study does not support the inclusion of a narrative leaflet at the preinvitation stage of the CRC Screening Programme, but further research could be developed to elucidate if narratives, in another format and/or position, could positively impact uptake of the CRC screening programme overall and reduce inequalities.
Specifically, there is evidence that creating additional reminder letters is associated with increasing uptake [
This pragmatic cluster randomised-trial found that providing a supplementary information leaflet, which presents a narrative account of the gFOBt-based, organised NHS CRC screening programme in England, neither increased overall uptake nor reduced inequalities, when delivered with the standard information material. This is despite the leaflet previously being found to significantly increase intentions to participate in CRC screening. The results do not support a change in policy at this time, but future research could investigate the impact of a stand-alone narrative leaflet at other points in the communication pathway.
Lesley M. McGregor and Christian von Wagner are joint first authors.
The views expressed in this paper are those of the authors and not necessarily those of the NHS, the National Institute for Health Research, or the Department of Health.
The authors declare that there is no conflict of interests regarding the publication of this paper.
This paper describes independent research funded by the National Institute for Health Research under its Programme Grants for Applied Research Programme (Grant reference no. RP-PG-0609-10106) and partly supported by the NIHR Collaboration for Leadership in Applied Health Research and Care (CLAHRC) North Thames (MCT and RR). The authors thank the managers of the screening hubs and staff at Real Digital International, Croydon, UK, for their oversight and management of the narrative intervention. They thank Paul Greliak, Imperial College London, and Cecily Palmer, University College London, for their contributions to the trial and project management, respectively. They also thank Hannah Chalkley, University College London, for her help in the collection of narratives, and Beating Bowel Cancer, Camden Carers Association, Public Health Partnerships, London, and, additionally, their patient representatives for their help and advice during the development of the narrative leaflet.