LAUSR

Abstract Background Uptake of the English Bowel Scope Screening (BSS) Programme is below the European target for acceptable participation, so that less than half of eligible adults currently benefit from the test. The aim of this study was to test the effectiveness of two self-referral reminders and a theory-based leaflet to improve uptake among former non-participants. Methods We performed a single-blind randomised controlled trial with three parallel arms at St Mark's Hospital, London, UK. Eligible adults were men and women who did not attend a BSS appointment at the centre within 12 months of their initial invitation. Individuals were randomised (1:1:1 ratio with simple pseudo-random allocation methods) to receive no reminder as per usual care (control), a self-referral reminder and standard information booklet (Rem-SIB), or a self-referral reminder and theory-based leaflet designed to address barriers to uptake (Rem-TBL). Individuals in both reminder groups were re-sent the self-referral reminder (with the allocated leaflet) if they had not taken part in screening within 24 months of their initial invitation. The primary outcome of the study was the proportion screened within each group 12 weeks after the delivery of the second self-referral reminder. The sample size was calculated with a standard test of difference between proportions. Analysis was by intention to treat with multivariable logistic regression on SPSS (version 24.0), with Bonferroni corrections to account for multiple comparisons. The study was approved by the Northeast Tyne and Wear South Research Ethics Service (Ref: 15/NE/0043). This trial is registered with the ISRCTN registry, number ISRCTN44293755. Findings 1383 adults were randomised to control (461), Rem-SIB (461), and Rem-TBL (461). Uptake was 0·7% (n=3), 14·5% (67), and 21·5% (99), respectively. Individuals in the Rem-SIB and Rem-TBL groups were significantly more likely to attend screening than individuals in the control group (adjusted odds ratio 26·1, 95% CI 8·1–84·0; p vs 46·9, 14·7–149·9; p Interpretation Reminders that targeted non-participants improved uptake, and use of theory-based information added substantially to this strategy. Further research is needed to test whether the findings apply outside the study setting. Funding St Mark's Hospital, Cancer Research UK