Nostradamus we are not, but a safe prediction for 2006 is that initiatives promoting public engagement in science and technology policy-making will proliferate. There will, of course, be devils in the details, and critical assessments will be required. But Nature, having consistently championed public engagement, can nevertheless only welcome its development.

But there are times when no amount of explanation and consultation can counter the resistance of some sectors of the public, often representing a strong current in society, to the most carefully crafted science-based advice. Because the stakes for people's quality of life, economic development and the rights of individuals can be high, governments and the rest of us need to understand how and why such resistance to science develops.

Studies by social scientists have a major role to play in providing an understanding of how such resistance develops. A notable example is British research led by Melissa Leach at the University of Sussex into strong resistance by parents to their children receiving a freely available vaccination against measles, mumps and rubella (MMR). The relevance of this research extends well beyond the particular circumstances and region studied.

The context was an outbreak in 1998 of public concern in Britain that the MMR vaccination might lead to autism in young children. The worries, which were stimulated by some scientists, proliferated and persisted despite increasingly robust reassurances from the government and clinicians that there was no epidemiological evidence for such a link.

The study of parents' responses provides a vivid demonstration of how people outside the relevant research communities develop their own knowledge and interpretation of the literature, and how the Internet allows this ‘lay expertise’ to be shared within a climate of shared perceptions of risk (see the unrefereed report MMR Mobilisation: Citizens and Science in a British Vaccine Controversy; For example, one parent, David Thrower, compiled his own review of the literature (, and several websites promptly supplied hostile responses to every government reassurance.

There is a strong case for a well-resourced independent agency that commands the trust of both the government and the public.

Leach's research highlights the influences on such resistance. Confounding stereotypes, the parents ranged across the social classes and in many cases displayed a sophisticated understanding of the issues. Surveys of parents on both sides of the debate revealed a significant association of those opposed to MMR with family histories of illness and with an interest in alternative medicines and homeopathy. There was a strong sense of responsibility among mothers of both persuasions about decisions over whether to have their children vaccinated, with concerns about the social value of vaccination in terms of herd immunity being given much lower priority.

The study's account of these developments is only partial, however. Close reading reveals an undercurrent of sympathy towards the parents and relatively cursory attention to attempts by the government and others to survey the evidence and respond to the parents' concerns. But the research is focused on the parents by definition, and provides an important starting point in trying to understand the various forces at work in a classic stand-off between citizens and science-based government advice.

Leach's work points to a conflict between concerns about MMR based on individual clinical studies versus government reassurances based on epidemiology. Soon after the publication of Leach's report, a meta-analysis of the literature on MMR by the prestigious Cochrane Collaboration, while highlighting shortcomings in many studies, concluded that there was a lack of evidence to support a link with autism ( A visit to one of the websites opposed to the MMR vaccine ( reveals a critique of the meta-analysis that attempts to undermine its reassurance. And so the debate continues. Meanwhile, the uptake of MMR vaccine, which fell significantly, is recovering.

In most countries, the departments of health are responsible for advising citizens on health matters. They, perhaps, have the most to gain from in-depth studies of public responses, while scientific academies may also find such accounts of alternative science sobering. But as happened with MMR, some key sectors of the public can lose faith in both the government and scientists. Thus there is a strong case for a well-resourced independent national agency that commands the trust of both the government and the public in matters of health protection and is empowered to take responsibility for mediating in such debates.

In addition to the unrefereed report, see M. Poltorak et al. Social Science and Medicine 61, 709–719; 2005.