Diffusion of Innovations

Diffusion is a multifaceted perspective about social change in which innovations are communicated over time among the members of a social system. Key to understanding this research and practice paradigm is acknowledgment of its emphasis on diffusion as (a) an inherently processual activity that occurs over time (see Figure 1), (b) the relations among people and their organizations as channels through which influence is exchanged in a network of social relations as individuals decide how to respond to an innovation they have previously learned about (see Figure 2), (c) perceptions by potential adopters of innovation characteristics that partly determine whether they will adopt the innovation or not, and (d) the enabling and constraining force of the sociomedia-environmental context in accounting for diffusion.

Scholars dating at least to the German social philosopher Georg Simmel and the French sociologist Gabriel Tarde theorized about imitative behavior at the level of small groups and within communities and the relation between these microlevel processes to macrolevel social change. In the 100 years since, researchers have tended to conceptualize diffusion either at the macrosociological level of sector, system, national, or state change; the social psychological or communicative level of local relationships and how those linkages affect adoption patterns as in a classic study by Elihu Katz and Paul Lazarsfeld; or the psychological level of how individuals perceive innovations in the form of a codified set of pros and cons. Beginning in the 1960s, diffusion concepts have been operational-ized and used to purposively spread prosocial innovations through development communication in Colombia, Pakistan, Brazil, Nigeria, India, Finland, Korea, Tanzania, Bolivia, and Vietnam.

Since 2000, diffusion studies have traced and explained the spread of kindergartens across cultures throughout the world, the spread of schools-of-choice policies among the 50 states in the United States, the diffusion of tobacco control policies back and forth between Canadian and U.S. political jurisdictions, the adoption of participatory approaches in community health system planning, the spread of e-commerce, and the online spread of social norms among adolescents. Studies such as these form the basis of the generalized codification of key concepts and the general pattern of diffusion over time from a literature of more than 5,500 publications as best synthesized by the communication scholar Everett M. Rogers in his successive editions of Diffusion of Innovations. Diffusion concepts have also contributed importantly to theoretical and conceptual development of social learning theory, technology transfer, dissemination strategy, social network theory, entertainment education, and now the science and practice of translational studies.

Figure 1 Diffusion is a nonlinear process of social influence over time.

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Figure 2 A sociogram of who seeks Advice from whom for a certain innovation

Notes: Arrows show advice-seeking directionality. The solid black node is the informal opinion leader. Innovations seeded by opinion leaders diffuse more rapidly and completely.