Improving adherence to colorectal cancer surveillance guidelines: Results of a randomised controlled trial

Background: Colorectal cancer (CRC) survivors are at increased risk of developing the disease again. Surveillance guidelines are aimed at maximising the early detection of recurring or new cancers and pre-cancerous polyps. The frequency and type of surveillance recommended depends on the type of treatment for the initial CRC, the extent of colonoscopic investigation prior to treatment and the results of previous surveillance tests. This paper aimed to test the effect of a paper-based educational intervention to improve adherence to colonoscopy following treatment for colorectal cancer. Methods: People with a diagnosis of colorectal cancer within the last 10 months, aged ≥18 and English speaking were recruited through a population-based cancer registry in Australia. Participants were randomly allocated to either the intervention or control. Participants completed an interview at baseline. Self-reported participation in colonoscopy was obtained at 12 month followup by survey. Those allocated to the control received a generic pamphlet on colorectal cancer treatment; while intervention participants received a letter which provided specific information about guideline recommendations for surveillance colonoscopy. Rates of guideline adherence were compared between groups. The guideline recommendations for the timing of surveillance colonoscopy changed part way through the study. This change occurred after all intervention materials had been sent, but prior to all participants completing the 12 month follow up. Post hoc analyses were conducted to assess adherence to the new guidelines. Results: Of the 767 participants, 604 (79%) had had surgery, had stage I - III disease and completed the baseline interview within 12 months of diagnosis (intervention = 305; control = 299). There was no significant difference between those adherent to surveillance colonoscopy guidelines, in the control (67, 27%) and intervention groups (80, 31%) at followup (difference = 4.3% (95%CI:-3.7%, 12%), χ ²(1df) = 1.09, P = 0.296). Overall, 246 (49%) participants were adherent to the new guidelines, compared to 147 (29%) adherent to the old guidelines. Conclusions: Results indicate the paper-based educational intervention is not effective in improving adherence to colorectal cancer surveillance guidelines for colonoscopy.