Evidence Maps in der Bewertung und Kommunikation von unsicheren Evidenzlagen

In this study, evidence maps are tested on the health effects of engineered nanoparticles for the first time. The study demonstrates that this method is highly suitable for assessing and graphically illustrating uncertain nanotoxicological evidence in relation to scientific standards and can help decision makers from outside the profession to understand the results. The study’s empirical testing of the comprehensibility of evidence maps for laypeople shows that the graphs present rather one-sided argumentation significantly better than narrative texts, but cannot do so for conflicting pieces of evidence – not even if the pro-risk arguments are weak. Nevertheless, the open presentation of uncertainties has a positive effect on their comprehensibility in experts’ assessment of the maps – the aversion to conflict is therefore stronger than the aversion to uncertainty. Whether online or in the form of PowerPoint presentations, evidence maps used at information events can help to explain the possible health risks of engineered nanoparticles.