• Late majority, who adopt the innovation mostly due to peer pressure

• Laggards, who are skeptical and resistant to change

This theory suggests that the adoption of new ideas by a select few will lead to a process of natural diffusion through which ideas spread throughout a community. Rogers also described how perceptions of the innovations can contribute to the adoption of a new practice. These perceptions include

• relative advantage (comparison of the innovation to current practice);

• compatibility (how the innovation fits with the adopter’s values, needs, etc.);

• complexity (difficulty of adopting the innovation);

• triability (if the innovation can be tested before full investment); and

• observability (whether others have successfully adopted the innovation) (Rogers, 2003).

Aside from these characteristics, a variety of other factors affect the adoption of new ideas, including both external factors (e.g., financial incentives and politics) and internal factors (e.g., competing priorities and resources) (IOM, 2006a). Finally, successful adoption of innovations demands commitment and a readiness for change as well as the support of organizational leadership in the adopting institution.

In the case of new models of care, dissemination has traditionally been slow and many models have been proved to be unsustainable (Leipzig et al., 2002; Reuben, 2002; Wolff and Boult, 2005). According to Rogers’s theory, a number of factors, if present, can be expected to improve the perception and potential appeal of new models of care for older patients. They include

• the model having an intuitive appeal;

• the existence of a strong evidence base demonstrating benefits for patients;

• potential cost savings;

• patient dissatisfaction with existing care; and

• secular trends, such as the aging of the population, recognition of the importance of managing chronic disease, and the move toward community-based care (Leff, 2007; Rogers, 2003).