Promoting Informed Decisions About Colorectal Cancer Screening in Older Adults (PRIMED Study): a Physician Cluster Randomized Trial

Document Type


Publication Date



Internal Medicine

Journal Title

Journal of general internal medicine


BACKGROUND: For adults aged 76-85, guidelines recommend individualizing decision-making about whether to continue colorectal cancer (CRC) testing. These conversations can be challenging as they need to consider a patient's CRC risk, life expectancy, and preferences. OBJECTIVE: To promote shared decision-making (SDM) for CRC testing decisions for older adults. DESIGN: Two-arm, multi-site cluster randomized trial, assigning physicians to Intervention and Comparator arms. Patients were surveyed shortly after the visit to assess outcomes. Analyses were intention-to-treat. PARTICIPANTS AND SETTING: Primary care physicians affiliated with 5 academic and community hospital networks and their patients aged 76-85 who were due for CRC testing and had a visit during the study period. INTERVENTIONS: Intervention arm physicians completed a 2-h online course in SDM communication skills and received an electronic reminder of patients eligible for CRC testing shortly before the visit. Comparator arm received reminders only. MAIN MEASURES: The primary outcome was patient-reported SDM Process score (range 0-4 with higher scores indicating more SDM); secondary outcomes included patient-reported discussion of CRC screening, knowledge, intention, and satisfaction with the visit. KEY RESULTS: Sixty-seven physicians (Intervention n=34 and Comparator n=33) enrolled. Patient participants (n=466) were on average 79 years old, 50% with excellent or very good self-rated overall health, and 66% had one or more prior colonoscopies. Patients in the Intervention arm had higher SDM Process scores (adjusted mean difference 0.36 (95%CI (0.08, 0.64), p=0.01) than in the Comparator arm. More patients in the Intervention arm reported discussing CRC screening during the visit (72% vs. 60%, p=0.03) and had higher intention to follow through with their preferred approach (58.0% vs. 47.1, p=0.03). Knowledge scores and visit satisfaction did not differ significantly between arms. CONCLUSION: Physician training plus reminders were effective in increasing SDM and frequency of CRC testing discussions in an age group where SDM is essential. TRIAL REGISTRATION: The trial is registered on (NCT03959696).