Introducing Root Cause Analysis framework to Colon Capsule Endoscopy (CCE) and updated evidence-based inclusion criteria

Background To improve uptake of colon-capsule-endoscopy (CCE) the test must have comparable outcomes to colonoscopy. Our aim was to identify any patient, technological or system factor that may be a source of poor test completion rates (CR). A secondary aim was to create evidence-based inclusion criteria using faecal immunochemical testing (FIT) to triage patients to CCE. Methods Utilising a root-cause-analysis (RCA) framework, 383 patients who underwent CCE in an NHS trust from May-December 2023 were analysed. Patients were separated into symptomatic and surveillance cohorts based on referral criteria. Demographics, comorbidities and medication were analysed for associations with a completed test and requirement for further procedure using univariate and multivariate logistic regression. For symptomatic patients, FIT values were also included for analysis. Results 327 symptomatic and 56 surveillance patients with mean age, female sex, completion rate and follow-up test rate were identified (58 vs 64 years, 60.5% vs 37.5%, 80.1% vs 80.3%, 55.7% vs 60.7%) respectively. In symptomatic patients, those prescribed hormone replacement therapy (HRT), loperamide and antihistamine medications or with a respiratory co-morbidity were more likely to have an incomplete test. FIT value had no bearing on test completion rate, type or likelihood to require follow-up and was a poor marker for the probability of detecting significant bowel disease (SBD – suspicion of cancer, polyp > 10mm or mucosal inflammation seen on CCE) (AUC = 0.58). In multivariate analysis, FIT values 10–79 µg/g, male sex and cardiovascular comorbidities were associated with higher odds for SBD compared to < 10 µg/g (Odds Ratio = 2.3 95% CI 1.09–5.01; p = 0.03). In the surveillance cohort, there were no significant associations identified between medical history, medication use and test completion rate. Conclusion Our study suggests there may be individual medications responsible for poor CCE completion rates but are of doubtful clinical significance. FIT should be performed prior to CCE but should not be used alone to predict outcomes or the likelihood of SBD. Inclusion criteria should be evidence based and CCE should aim to target a low-risk population. This root cause analysis indicates that the next key area of investigation should be the capsule technology itself.