History

The concept of diffusion was first studied by the French sociologist Gabriel Tarde in late 19th century[2] and by German and Austrian anthropologists such as Friedrich Ratzel and Leo Frobenius.[3] Its basic epidemiological or internal-influence form was formulated by H. Earl Pemberton,[4] who provided examples of institutional diffusion such as postage stamps and standardized school ethic codes.

In 1962 Everett Rogers, a professor of rural sociology published his work: "Diffusion of Innovations". In this seminal piece, Rogers synthesized research from over 508 diffusion studies and produced a theory applied to the adoption of innovations among individuals and organizations.

Roger's work asserts that 4 main elements influence the spread of a new idea: the innovation, communication channels, time, and a social system. These elements work in conjunction with one another: diffusion is the process by which an innovation is communicated through certain channels over time among the members of a social system. Rogers adds that central to this theory is process. Individuals experience 5 stages of accepting a new innovation: knowledge, persuasion, decision, implementation, and confirmation. If the innovation is adopted, it spreads via various communication channels. During communication, the idea is rarely evaluated from a scientific standpoint; rather, subjective perceptions of the innovation influence diffusion. The process occurs over time. Finally, social systems determine diffusion, norms on diffusion, roles of opinion leaders and change agents, types of innovation decisions, and innovation consequences. To use Rogers’ model in health requires us to assume that the innovation in classical diffusion theory is equivalent to scientific research findings in the context of practice, an assumption that has not been rigorously tested. How can we spread and sustain innovations in health service delivery and organization? Greenhalgh et al., evaluate an evidence-based model for considering the diffusion of innovations in health service organizations.[5]

The origins of the diffusion of innovations theory are varied and span across multiple disciplines. Rogers identifies six main traditions that impacted diffusion research: anthropology, early sociology, rural sociology, education, industrial sociology, and medical sociology. The diffusion of innovation theory has been largely influenced by the work of rural sociologists.[6] In 1971, Rogers published a follow-up work: Communication of Innovations; A Cross-Cultural Approach. building on his original theory on the diffusion process by evaluating social systems. This extension aimed to add value to Roger’s 1962 touchstone work (Rogers & Shoemaker, 1971).