Effects of evidence-based strategies to reduce the socioeconomic gradient of uptake in the English NHS Bowel Cancer Screening Programme (ASCEND): four cluster-randomised controlled trials

Abstract

SummaryBackgroundUptake in the national colorectal cancer screening programme in England varies by socioeconomic status. We assessed four interventions aimed at reducing this gradient, with the intention of improving the health benefits of screening.MethodsAll people eligible for screening (men and women aged 60–74 years) across England were included in four cluster-randomised trials. Randomisation was based on day of invitation. Each trial compared the standard information with the standard information plus the following supplementary interventions: trial 1 (November, 2012), a supplementary leaflet summarising the gist of the key information; trial 2 (March, 2012), a supplementary narrative leaflet describing people's stories; trial 3 (June, 2013), general practice endorsement of the programme on the invitation letter; and trial 4 (July–August, 2013) an enhanced reminder letter with a banner that reiterated the screening offer. Socioeconomic status was defined by the Index of Multiple Deprivation score for each home address. The primary outcome was the socioeconomic status gradient in uptake across deprivation quintiles. This study is registered, number ISRCTN74121020.FindingsAs all four trials were embedded in the screening programme, loss to follow-up was minimal (less than 0·5%). Trials 1 (n=163 525) and 2 (n=150 417) showed no effects on the socioeconomic gradient of uptake or overall uptake. Trial 3 (n=265 434) showed no effect on the socioeconomic gradient but was associated with increased overall uptake (adjusted odds ratio [OR] 1·07, 95% CI 1·04–1·10, p<0·0001). In trial 4 (n=168 480) a significant interaction was seen with socioeconomic status gradient (p=0·005), with a stronger effect in the most deprived quintile (adjusted OR 1·11, 95% CI 1·04–1·20, p=0·003) than in the least deprived (1·00, 0·94–1·06, p=0·98). Overall uptake was also increased (1·07, 1·03–1·11, p=0·001).InterpretationOf four evidence-based interventions, the enhanced reminder letter reduced the socioeconomic gradient in screening uptake, but further reducing inequalities in screening uptake through written materials alone will be challenging.FundingNational Institute for Health Research.

Socioeconomic and ethnic inequities within organised colorectal cancer screening programmes worldwide

“…For example, Wardle et al showed that implementing an enhanced reminder letter in England's CRC screening programme increased participation, with stronger effect in the most deprived quintile. Within this study, tailored information material interventions such as summarising leaflets, narrative leaflets with ‘people's stories’ and endorsement letters did however not influence screening participation by socioeconomic gradient 59. McGregor et al concluded the same ineffectiveness on socioeconomic uptake with the implementation of an additional narrative leaflet containing ‘individual experienced screening stories’ 60.…”

Concerns, perceived need and competing priorities: a qualitative exploration of decision-making and non-participation in a population-based flexible sigmoidoscopy screening programme to prevent colorectal cancer

“…Intervention studies incorporating factors such as general practitioner (GP) endorsement,15 reminders and social networks have shown these can have a positive effect on uptake. However, the evidence is inconsistent,16 17 and effectiveness is likely to be, in part, influenced by the healthcare context in which the intervention is based. The dynamics of decision-making for FS screening may be quite different, with its high technology, specialist-based approach, a less proactive role required for participants and a different method of invitation.…”

Colorectal cancer screening: Opportunities to improve uptake, outcomes, and disparities

“…In a 2009 study assessing Medicare enrollees ages 65 to 80 years, individuals less educated or belonging to low-income groups were less likely to undergo CRC screening[80]. Unfortunately, even when the cost of CRC screening is alleviated, disparity still persists[81]. In England, the Bowel Cancer Screening Program does not pose any financial costs to participants because it is operated by the National Health Service since 2006.…”