Shared decision-making (SDM) has been advocated as strategy for increasing colorectal cancer (CRC) screening rates. The overall objective of this study is to assess whether the development of a risk prediction model for advanced colorectal neoplasia is a feasible and valid strategy for facilitating effective SDM and improving the cost-effectiveness of screening colonoscopy. In Aim #1, we propose to conduct a cross- sectional survey of 4000 asymptomatic patients undergoing screening colonoscopy for the purpose of developing a prediction model based on putative modifiable and non-modifiable risk factors that stratifies patients into distinct risk categories for advanced colorectal neoplasia. Subjects will be asked to complete a brief risk assessment questionnaire prior to their examination;responses will be correlated with endoscopic findings. Once derived, we will evaluate the model's performance characteristics among a racially/ethnically diverse patient population (n=1200). Aim #2 is to adapt the model for use as a decisional support tool for primary care physicians who engage in SDM when discussing CRC screening with their patients. We propose to use qualitative and quantitative methods to examine factors that influence provider decision-making, assess provider numeracy skills, and identify thresholds for defining risk categories. Once defined, we will translate the model into a web-based risk assessment tool capable of generating patient-derived risk estimates with acceptable framing that optimizes risk communication. Pre-implementation seminars will be conducted to train providers in use of the tool, appropriate documentation in the medical record and strategies for communicating risk to patients. Aim #3 is to conduct a clinical trial to determine whether risk stratification influences clinical decision-making related to screening test selection within a SDM framework. Eligible subjects (n=440) will be randomized to complete the risk assessment tool or not prior to reviewing a web-based decision aid describing the pros and cons of the five recommended CRC screening options. Both interventions will take place just before a prearranged office visit with their provider. The primary outcome will be screening test ordered;secondary outcomes will include test completion rates, value concordance, patient satisfaction with decision- making process and provider satisfaction. Outcomes will be evaluated using computerized tracking systems or validated instruments. Aim #4 is to determine the cost-effectiveness of risk-based use of screening colonoscopy compared to universal use of screening colonoscopy and other currently recommended screening strategies. PUBLIC HEALTH RELEVANCE: Shared decision-making (SDM) has been advocated as strategy for increasing colorectal cancer (CRC) screening rates. The development of a valid risk prediction model for advanced colorectal neoplasia would enable providers to incorporate risk estimates into their decision-making when recommending a preferred screening option, thus facilitating more effective SDM and improving the cost-effectiveness of screening colonoscopy.