Background
Diffusion research goes one step further than two-step flow theory. The original diffusion research was done in the early 1900s by the French sociologist Gabriel Tarde who plotted the original S-shaped diffusion curve. Tardes' 1903 S-shaped curve is of current importance because "most innovations have an S-shaped rate of adoption" (Rogers, 1995).
Diffusion research deals with the conditions which increase or decrease the likelihood that a new idea, product, or practice will be adopted by members of a given culture.
Diffusion of innovation theory predicts that media as well as interpersonal contacts provide information and influence opinion and judgment.
E.M. Rogers (1995) posited that the theory consists of four stages: invention, diffusion (or communication) through the social system, time and consequences. The information flows through networks. The nature of networks and the roles opinion leaders play in them determine the likelihood that the innovation will be adopted.
Innovation diffusion research has attempted to explain the variables that influence how and why users adopt a new information medium, such as the Internet.
Opinion leaders exert influence on audience behaviour through their personal contact, but additional intermediaries called change agents and gatekeepers are also included in the process of diffusion.
Five adopter categories are: (1) innovators, (2) early adopters, (3) early majority, (4) late majority, and (5) laggards. These categories follow a standard deviation-curve, very little innovators adopt the innovation in the beginning (2,5%), early adopters making up for 13,5% a short time later, the early majority 34%, the late majority 34% and after some time finally the laggards make up for 16%.
Diffusion is the “process by which an innovation is communicated through certain channels over a period of time among the members of a social system”. An innovation is “an idea, practice, or object that is perceived to be new by an individual or other unit of adoption”. “Communication is a process in which participants create and share information with one another to reach a mutual understanding” (Rogers, 1995).
Conceptual Model
Some of the methods are network analysis, surveys, field experiments and ECCO analysis. ECCO, Episodic Communication Channels in Organization, analysis is a form of a data collection log-sheet. This method is specially designed to analyze and map communication networks and measure rates of flow, distortion of messages, and redundancy.
The ECCO is used to monitor the progress of a specific piece of information through the organization.
Scope and Application
Diffusion research has focused on five elements: (1) the characteristics of an innovation which may influence its adoption; (2) the decision-making process that occurs when individuals consider adopting a new idea, product or practice; (3) the characteristics of individuals that make them likely to adopt an innovation; (4) the consequences for individuals and society of adopting an innovation; and (5) communication channels used in the adoption process.
Limitations of Diffusion Innovation Theory
Below are some limitations of Diffusion of Innovation:
• Majority of the evidence for this theory, including the adopter categories, did not originate in public health and it was not developed to explicitly apply to adoption of new behaviours or health innovations.
• It does not promote a participatory approach to adoption of a public health program.
• It works better with adoption of behaviours rather than cessation or prevention of behaviours.
