Return to bowel screening after a false-positive faecal immunochemical test in BowelScreen (the National Bowel Screening Programme in Ireland)

Objective Little research exists on what predicts individual return to screening after a false-positive faecal immunochemical test in a population bowel screening programme. We aimed to quantify the impact of false-positive faecal immunochemical test in the first round of screening on re-attendance in BowelScreen, the National Bowel Screening Programme in Ireland. Methods A retrospective cohort study was conducted. False-positivity was defined as a positive faecal immunochemical test with subsequent colonoscopy showing no evidence of malignancy or surveillance requirement. In those with a false-positive faecal immunochemical test, logistic regression was used to predict repeat participation in the second round. Results Of 196,149 individuals who attended the first screening round, 108,075 were eligible and re-invited in the second round, and 93,971 accepted the invitation (86.9%). Second round uptake was higher in faecal immunochemical test-negative individuals compared with those having false-positive results (87.5% vs. 73.1%; p < 0.001). Older age (odds ratio (OR) 0.75; 95% confidence interval (CI) 0.60-0.94), computed tomography colonography (unsuitability/failed colonoscopy) (OR 0.40; 95% CI 0.21-0.73), and longer duration from screening invitation to faecal immunochemical test result (OR 0.991; 95% CI 0.9872-0.995) were predictors of non-re-attendance in the next screening round. Conclusion There is a significant reduction in re-attendance rates for individuals with false-positive faecal immunochemical test results. The letter sent following a negative colonoscopy is being reviewed to ensure that it provides adequate encouragement to re-attend. There are roles for screening promotion and for Gastroenterologists and Advanced Nurse Practitioners to emphasize the importance of regular faecal immunochemical tests after a negative colonoscopy.