Effect of Patient Navigation on Screening Colonoscopy Completion among High-Risk Participants: Protocol for a Randomized Trial
MEJIA PEREZ C. 1,2, PLYS E. 1,2, BETTICHER D. 3, DERTSCHNIG S. 4,5, DURAND M. 1,2,6, FREUD R. 1,2, HAAG M. 7, HESS V. 7, SCHWENKGLENKS M. 8, TOMONAGA Y. 9, WISNIAK A. 10, SELBY K. 1,2
1 Unisanté, University Center for Primary Care and Public Health, Lausanne, Switzerland; 2 University of Lausanne, Lausanne, Switzerland; 3 Cancer screening program of the canton of Fribourg, Fribourg, Switzerland; 4 Cancer screening program of the canton of Bern, Bern, Switzerland; 5 Cancer screening program of the cantons of both Basels, Basel, Switzerland; 6 The Dartmouth Institute for Health Policy and Clinical Practice, Dartmouth College, Lebanon, United States; 7 University Hospital Basel and University of Basel, Basel, Switzerland; 8 Health Economics Facility, Department of Public Health, University of Basel, Basel, Switzerland; 9 Epidemiology, Biostatistics and Prevention Institute (EBPI), University of Zurich, Zurich, Switzerland; 10 Cancer screening program of the canton of Geneva, Geneva, Switzerland
Background: Randomized controlled trials (RCTs) primarily conducted in the United States have shown that barrier-oriented interventions delivered by telephone, such as navigation, can provide an 18% absolute increase in colonoscopy uptake (relative risk [RR] 2.01). However, there is limited evidence on the effectiveness of navigation for increasing colonoscopy uptake in European screening programs.
Studies suggest that risk-based screening – which provides individuals with their estimated colorectal cancer (CRC) risk alongside clear recommendations – can guide participants toward appropriate screening tests while maintaining overall participation rates. Navigation for colonoscopy may also be an effective way to improve CRC screening. However, organized screening programs remain reluctant to adopt interventions developed abroad because of limited data on cost-effectiveness and needed resources.
This study is a secondary objective of PRESENT-CRC, a 3-arm RCT conducted in five Swiss cantons and aiming to evaluate the effectiveness of risk-based CRC screening (ISRCTN10525659). Participants randomized in the intervention arm will receive personalized CRC risk assessment and screening recommendations: a fecal immunochemical test (FIT) will be recommended for participants with a 0-3.9% risk and colonoscopy will be recommended for participants with a risk of 4% or higher (calculated with QCancer-colorectal 15-year risk calculator). Half of the intervention group participants at higher risk will receive navigation, the other half will receive risk-based recommendations alone.
Objectives: Our primary objective is to assess whether patient navigation increases colonoscopy uptake among higher-risk participants 1-year post-randomization, compared with higher-risk participants who are not offered navigation. We also aim to explore barriers to colonoscopy; to estimate the cost-effectiveness of navigation; and to identify the most practical methods of reaching participants (telephone, email or text messages).
Methods: Our navigation guide is based on the New Hampshire Colorectal Cancer Screening Program (NHCRCSP) Patient Navigation model and focuses on patient engagement, CRC screening education, and barrier assessment (the NHCRCSP topic 1). We conducted semi-structured interviews with participating screening programs to assess the feasibility and acceptability of our approach. Navigators will be employees of the screening programs who will complete a half-day training session on the navigation guide provided by the research team.
Study participants will include PRESENT-CRC trial participants aged between 50 to 74 years eligible for CRC screening and classified as higher risk. Participants who have not completed a colonoscopy within four months after the trial intervention will be contacted by the navigators via phone calls, text messages and emails. Each participant will be offered a brief 10-to-20-minutes interview.
Expected results: We expect to have 80% power to detect a 10% increase in colonoscopy completion (RR 1.26) in higher-risk participants who are offered navigation compared with higher-participants who are not. We also expect that navigation will increase costs and quality-adjusted life-years (QALY’s) gained as compared to risk-based screening recommendations alone, with an acceptable incremental cost-effectiveness ratio (ICER).
Conclusion/Implications: Navigation targeted at higher-risk participants represents a powerful lever for organized screening programs to improve colorectal cancer screening uptake and achieve direct health benefits.