For the first time researchers from Nottingham Trent University have investigated the way in which the general public determine health risks of diseases that have no scientific evidence.
Research conducted by Professor Louise Cummings, a linguist in the university’s School of Arts and Humanities, has revealed the type of perception individuals without expert knowledge use to determine health risks.
More than 750 members of the general public completed a survey which consisted of a variety of short paragraphs regarding real and made-up public health scenarios. Participants were then asked questions which required them to create assessments about each of the scenarios.
The researchers designed the scenarios to mirror conditions under which individuals typically determine health risks. Little scientific evidence was presented to participants for them to form their assessment, a situation which replicates their lack of knowledge when evaluating health risks on a daily basis. For example, in one scenario participants were asked to make an assessment regarding scientists who reasoned that as no evidence was found that a food additive was harmful, it was therefore considered safe, or, in another scenario, due to the similarity between bovine spongiform encephalopathy (BSE) and scrapie in sheep, BSE will behave in the same way as scrapie.
The researchers discovered that participants used trust in scientific experts to base their own judgment of health risks under certain conditions. Furthermore, they found that participants consistently identified genuine or impartial expertise as a valid basis for their own judgment. However when, for example, participants perceived scientists to be tainted by commercial interests, they were less influenced to defer to such experience in their own assessment.
The researchers also found participants were capable of using features of one disease as a basis for conclusions about another when assessing two sufficiently similar diseases. As an example, participants judged that the similarity of infected populations in HIV/AIDS and hepatitis B provided a sufficiently strong basis for them to conclude that a blood-borne virus was the causal agent responsible for early AIDS deaths. Researchers discovered that participants also had the ability to base features of a new disease upon features of a pre-existing disease when two diseases were not sufficiently similar, for example, many established that in the absence of strain-typing studies, scrapie in sheep would not provide a reliable model of how BSE would behave.
Professor Cummings, explained:
“Public health is a wide-ranging area of work involving issues as diverse as the outbreak of infections diseases, the effects of exposure to chemicals in the environment, food risks and the safety of vaccinations and other prescribed medications. These issues affect our daily lives and require us to make assessments of them, even though we may lack the subject knowledge of expert scientists.
Academic literature in fields such as health psychology has given us insights into how people assess health risks when these are presented in a numerical format and can at least be quantified. However, many health risks cannot be quantified, especially when they emerge for the first time. This study has revealed the reasoning strategies that people use to bridge their lack of knowledge and arrive at judgments. It shows that people are skilled at using certain cognitive shortcuts to help them form judgments about complex health-related issues when they lack the related knowledge.”
The results of this investigation will assist public health professions to understand how individuals of the general public evaluate health risks. Furthermore, the study will help enable them to create health messages in ways the general public are more likely to support and understand.
Written by: Grace Rattue