The spread of influenza A subtype H5N1 has recently heightened pandemic concern and preparedness for a pandemic influenza virus has become a global priority. Research in risk communication emphasizes the importance of providing the recipients with information they need to make informed independent judgments. This entails understanding how these judgments are made, and what kind of information that serves this purpose. Decisions have been examined in a wide variety of scientific disciplines and produced several interesting methods and models to understand judgment and decisions. These methods and models were investigated and compared with regard to their fit to these conditions.The work in this thesis was oriented toward three main questions. The first question was how to find out how people would react during an emergency. The second question was what kind of research in decision theory could explain and be used to predict these results. The third question was whether a mental model of the threat of pandemic influenza can be described, and what is its implication on risk communication.A mental model approach to explore risk communications was used with qualitative interviews with health care workers in Östergötland, Sweden. The transcripts were analyzed according to methods drawn from mental models research and risk communication to extract influence diagrams. These influence diagrams serves as an abstract representation of the respondents’ mental model of the threat of pandemic influenza. This influence diagram was compared to a corresponding expert mental model developed from literature and interviews with influenza experts.The mental models approach has been shown to provide a description of comprehension with several benefits. One benefit is that the method is a relatively easy way to gather notions in the target population which can be used for drafting risk information. Another benefit is that the existing notions and sense of causal patterns can be described, instead of merely memorized facts.The comparison between the mental models of health care workers and influenza experts revealed both functional and destructive misconceptions. Unrelated informatio...
