1. Deficit Model of Science Communication

The original term ‘deficit model’ was coined in the 1980s by social scientists studying the public communication of science. The purpose of the phrase was not to introduce a new mode of science communication but rather it was to characterise a widely held belief that underlies much of what is carried out in the name of such activity.

There are two aspects to this belief. The first is the idea that public uncertainty and scepticism towards modern science including environmental issues and technology is caused primarily by a lack of sufficient knowledge about science and the relevant subjects. The second aspect relates to the idea that by providing the adequate information to overcome this lack of knowledge, also known as a ‘knowledge deficit’, the general public opinion will change and decide that the information provided on the environment and science as a whole is reliable and accurate.^[1]

Scientists are often heard to complain that the general public does not understand science, and that the public needs to be educated. In the deficit model scientists assume that there is a knowledge deficit that can be ‘fixed’ by giving the public more information: scientists often assume that “given the facts (whatever they are), the public will happily support new technologies.”^[2]

The deficit model, however, has been discredited by a wealth of literature that shows that simply giving more information to people does not necessarily change their views.^[3] This is partly because people want to feel that they have had their say (and have been heard) in any decision-making process, and partly because people make decisions based on a host of factors as well as the scientific ‘facts’. These factors include ethical, political, and religious beliefs, in addition to culture, history and personal experience. This amounts to a kind of gut feeling, which scientific facts are unlikely to change. Put another way, people's sense of risk extends beyond the purely scientific considerations of conventional risk analysis, and the deficit model marginalises these ‘externalities’. It is now widely accepted that the best alternative to deficit model thinking is to genuinely engage with the public and take these externalities into account.^[4]

This has led science communicators, particularly those seeking to address unsubstantiated beliefs, to look for alternative methods of persuasion. A 2019 study, for example, showed that exposure to the stories of an individual converted from opposing to supporting genetically modified organisms led to more positive attitudes toward GMOs.^[5]

The deficit model sees the general population as the receiver of information and scientific knowledge. The information they receive, through whatever medium, has been prearranged to inform them of information that the distributors believe to be in the public's interest. Due to the recent growth of scientific research and subsequent discoveries, the deficit model suggests that this has led to a decrease in interest surrounding certain areas of science. This can be down to the public feeling overwhelmed with information and becomes uninterested, as it appears too much to take in.

The deficit model of scientific understanding makes assumptions about the public's knowledge. The model perceives them to be “blank slates” where their knowledge of scientific discourse and research is almost non-existent.^[6] Again, this is the knowledge deficit that needs to be informed by a reliable, knowledgeable and hierarchical scientific community in the form of simple commands and generic instructions. But the increase in new information systems such as the Internet and their ease of accessibility has led to a greater knowledge of scientific research and this is evident as the public's understanding can be seen to be growing. This is a good thing in terms of the members of the public that can actively increase their own knowledge base, decrease the knowledge deficit and assess the truth and validity of what mass media outlets and governments are telling them. This should enhance and increase the relationship between the passive “blank slates” of the public, with the minority of the population who hold the ‘knowledge surplus’.

1.1. Evidence for a Deficit Affecting Opinion

A 2008 meta-analysis of 193 studies sought to interpret the link between science knowledge and attitude towards science.^[7] The studies included were taken using nonuniform methods across the world between 1989 and 2004 to provide a cross-cultural analysis. Broad and specific science knowledge and attitude categories were correlated. General science and general biology knowledge was gauged using questions similar to those by the National Science Foundation used to capture "civil scientific literacy".^[8] Data on general science and biology knowledge was then compared with attitudes towards general science, nuclear power, genetic medicine, genetically modified food, and environmental science. From the raw data, it was found that a small positive correlation exists between general science knowledge and attitude towards science, indicating that increased scientific knowledge is related to a favorable attitude towards a science topic, and that this was not related to socioeconomic or technologic status of a country, but rather the number of individuals enrolled in tertiary education. However, some studies have found that high levels of science knowledge may indicate highly positive and highly negative attitudes towards specific topics such as agriculture biotechnology.^[9] Thus knowledge may be a predictor of the attitude strength and not necessarily if the attitude is positive or negative.

1.2. Evidence against the Deficit Model

While knowledge may influence attitude strengths, other studies have shown that merely increasing knowledge does not effectively augment public trust in science.^[10] In addition to scientific knowledge, the public uses other values (i.e. religion) to form heuristics and make decisions about scientific technology. These same values may cloud responses to questions probing the public's scientific understanding, an example being evolution. On the National Science Foundation Indicators, less than half (~45%) of Americans agreed that humans evolved from other species. This is much lower than reports from other countries, and was interpreted as a deficit in scientific literacy. However, when a qualifier was added ("according to the theory of evolution..."), 72% of Americans correctly answered that humans evolved from other species.^[11] Therefore, knowledge alone does not explain public opinions with regard to science. Scientists must take other values and heuristics into account when communicating with the public in order to maintain trust and deference. In fact, some have called for more democratic accountability for bioethicists and scientists, meaning public values would feedback onto the progression/acceptance of scientific technology.^[12] Emerging evidence suggests that this public/science collaboration may even be rewarding for researchers: 82% of faculty surveyed in a 2019 study agreed that getting "food for thought" from their public audiences was a positive outcome from public engagement activities.^[13] As attention among the academics starts shifting back towards an emphasis on public engagement, organizations like the American Association for the Advancement of Science (AAAS) have therefore called for "intentional, meaningful interactions that provide opportunities for mutual learning between scientists and members of the public".

2. The Role of the Media

Mass media representations, ranging from news to entertainment, are critical links between the everyday realities of how people experience certain issues and the ways in which these are discussed at a distance between science, policy and public actors.^[1] Numerous studies show that the public frequently learn about science and more specifically issues such as climate change from the mass media.

There is perceived to be a trend within much of the world's media that a traditional commitment to report the full facts is and has given way to a more obvious, less reliable tendency to concentrate coverage on interpretations of the facts. This so-called ‘spin’ is reported by the world's press under a combination of commercial and political pressure. This can be dangerous as it ‘fills’ the knowledge deficit and the unsuspecting public with sometimes unreliable, agenda promoting information. The subjects of anthropogenic global warming and climate change are at the forefront of this. However, in all cases it is becoming increasingly difficult to separate out the factual basis of what is being reported from the ‘spin’ that is exerted on the way a story is reported and presented.^[2]

The mass media is accessible to the vast numbers of the global population and ranging from entertainment, to news media, and spanning books, films, televisions, newspapers, radio, games and the Internet. More modern forms of communication and receiving of information have given the public a much wider and accessible format in which to gain knowledge themselves.

The actual processes behind the communication and dissemination of information from the experts to the public may be far more complex and deep running than the deficit model suggests.

The knowledge deficit model is important for science communicators to know about. This is particularly important with respect to the concept of framing when communicating information. Framing can be used to reduce the complexity of an issue, or to persuade audiences, and can play into the underlying religious beliefs, moral values, prior knowledge, and even trust in scientists or political individuals. Further, the transmission of scientific ideas and technological adoption may be strongly linked to the passage of information between easily influenced individuals,^[14] versus the widely accepted "two-step flow" theory where a few opinion leaders acted as intermediaries between mass media and the general public.^[15] Decreasing the knowledge deficit is a complicated task, but if we know how the general public thinks, or how they go about learning and interpreting new information, we can better communicate our message to them in the most unbiased, objective way possible.^[16]

3. Alternative Models

In contrast to the knowledge-deficit model is the low-information rationality model that states humans minimize costs associated with making decisions and forming attitudes, thereby avoiding developing in-depth understandings.