A randomized trial of genetic and environmental risk assessment (GERA) for colorectal cancer risk in primary care: Trial design and baseline findings

Purpose: This paper describes an ongoing randomized controlled trial designed to assess the impact of genetic and environmental risk assessment (GERA) on colorectal cancer (CRC) screening. Methods: The trial includes asymptomatic patients who are 50-79. years and are not up-to-date with CRC screening guidelines. Patients who responded to a baseline telephone survey are randomized to a GERA or Control group. GERA group participants meet with a nurse, decide whether to have a GERA blood test (a combination of genetic polymorphism and folate), and, if tested, receive GERA feedback. Follow-up telephone surveys are conducted at 1 and 6. months. A chart audit is performed at 6. months. Results: Of 2,223 eligible patients, 562 (25%) have enrolled. Patients who enrolled in the study were significantly younger than those who did not ( p< 0.001). Participants tended to be 50-59. years (64%), female (58%), white (52%), married (51%), and have more than a high school education (67%). At baseline, most participants had some knowledge of CRC screening and GERA, viewed CRC screening favorably, and reported that they had decided to do screening. Almost half had worries and concerns about CRC. Conclusions: One in four eligible primary care patients enrolled in the study. Age was negatively associated with enrollment. Prospective analyses using data for all participants will provide more definitive information on GERA uptake and the impact of GERA feedback.