Assessments of medical technologies with respect to their efficacy, safety, and cost-effectiveness are expected to influence clinical practice, but they are often lost in an avalanche of medical information. We developed a conceptual model that may aid understanding of the potential impact on clinical practice of new medical information in general and assessment information in particular. The model identifies aspects of medical communication that may influence an assessment's subsequent impact, including sources, messages, channels, audiences, and settings. We reviewed the literature on how medical information diffuses to physicians and highlighted those factors likely to heighten physicians' awareness and decisions to incorporate recommended medical advances. We outlined implications for educational interventions and promising research directions.