Diminishing Willingness to Pay per Quality‐Adjusted Life Year: Valuing Acute Foodborne Illness

We design and conduct a stated‐preference survey to estimate willingness to pay (WTP) to reduce foodborne risk of acute illness and to test whether WTP is proportional to the corresponding gain in expected quality‐adjusted life years (QALYs). If QALYs measure utility for health, then economic theory requires WTP to be nearly proportional to changes in both health quality and duration of illness and WTP could be estimated by multiplying the expected change in QALYs by an appropriate monetary value. WTP is elicited using double‐bounded, dichotomous‐choice questions in which respondents (randomly selected from the U.S. general adult population, n = 2,858) decide whether to purchase a more expensive food to reduce the risk of foodborne illness. Health risks vary by baseline probability of illness, reduction in probability, duration and severity of illness, and conditional probability of mortality. The expected gain in QALYs is calculated using respondent‐assessed decrements in health‐related quality of life if ill combined with the duration of illness and reduction in probability specified in the survey. We find sharply diminishing marginal WTP for severity and duration of illness prevented. Our results suggest that individuals do not have a constant rate of WTP per QALY, which implies that WTP cannot be accurately estimated by multiplying the change in QALYs by an appropriate monetary value.     

Intended Message Versus Message Received in Hypothetical Physician Risk Communications: Exploring the Gap

We examined the risk perception that is derived from hypothetical physician risk communications. Subjects (n= 217) completed a questionnaire on the Web for $3. Subjects were presented with four hypothetical cancer risk scenarios that included a physician risk communication in one of three risk communication formats: verbal only, verbal plus numeric probability as a percent, and verbal plus numeric probability as a fraction. In each scenario, subjects were asked to imagine themselves as the patient described and to state their perceived personal susceptibility to the cancer (i.e., risk perception) on a 0 to 100 scale, as well as responses to other measures. Subjects' risk perceptions were highly variable, spanning nearly the entire probability scale for each scenario, and the degree of variation was only slightly less in the risk communication formats in which a numeric statement of risk was provided. Subjects were more likely to overestimate than underestimate their risk relative to the stated risk in the numeric versions, and overestimation was associated with the belief that the physician minimized the risk so they wouldn't worry, innumeracy, and worry, as well as decisions about testing for the cancer. These results demonstrate significant gaps between the intended message and the message received in physician risk communications. Implications for medical decisions, patient distress, and future research are discussed.     

Risk Perception and Communication Unplugged: Twenty Years of Process1

Over the past twenty years, risk communication researchers and practitioners have learned some lessons, often at considerable personal price. For the most part, the mistakes that they have made have been natural, even intelligent ones. As a result, the same pitfalls may tempt newcomers to the field. This essay offers a personal (even confessional) history of the field over this period. It identifies a series of developmental stages. Progress through the stages involves consolidating the skills needed to execute it and learning its limitations. Knowing about their existence might speed the learning process and alert one to how much there still is to learn.     

Growing Pains: How Risk Perception and Risk Communication Research Can Help to Manage the Challenges of Global Population Growth

In 2011, the global human population reached 7 billion and medium variant projections indicate that it will exceed 9 billion before 2045. Theoretical and empirical perspectives suggest that this growth could lead to an increase in the likelihood of adverse events (e.g., food shortages, climate change, etc.) and/or the severity of adverse events (e.g., famines, natural disasters, etc.). Several scholars have posited that the size to which the global population grows and the extent to which this growth increases the likelihood of adverse outcomes will largely be shaped by individuals’ decisions (in households, organizations, governments, etc.). In light of the strong relationship between perceived risk and decision behaviors, it is surprising that there remains a dearth of empirical research that specifically examines the perceived risks of population growth and how these perceptions might influence related decisions. In an attempt to motivate this important strand of research, this article examines the major risks that may be exacerbated by global population growth and draws upon empirical work concerning the perception and communication of risk to identify potential directions for future research. The article also considers how individuals might perceive both the risks and benefits of population growth and be helped to better understand and address the related issues. The answers to these questions could help humanity better manage the emerging consequences of its continuing success in increasing infant survival and adult longevity.     

Nanotechnology Risk Communication Past and Prologue

Nanotechnologies operate at atomic, molecular, and macromolecular scales, at scales where matter behaves differently than at larger scales and quantum effects can dominate. Nanotechnologies have captured the imagination of science fiction writers as science, engineering, and industry have leapt to the challenge of harnessing them. Applications are proliferating. In contrast, despite recent progress the regulatory landscape is not yet coherent, and public awareness of nanotechnology remains low. This has led risk researchers and critics of current nanotechnology risk communication efforts to call for proactive strategies that do more than address facts, that include and go beyond the public participation stipulated by some government acts. A redoubling of nanotechnology risk communication efforts could enable consumer choice and informed public discourse about regulation and public investments in science and safety.     

Agency Communication, Community Outrage, and Perception of Risk: Three Simulation Experiments

Three experimental studies were conducted employing hypothetical news stories to compare the effects on reader risk perceptions of two situations: when agency communication behavior was reported to be responsive to citizens' risk concerns, vs. when the agency was reported to be unresponsive. In the first two experiments, news stories of public meetings filled with distrust and controversy led to ratings indicating greater perceived risk than news stories reporting no distrust or controversy, even though the risk information was held constant. This effect appeared clearly when the differences in meeting tone were extreme and subjects made their ratings from their recall of the stories, but it was much weaker when the differences were moderate and subjects were allowed to go back over the news stories to help separate risk information from conflict information. In the third experiment, news stories about a spill cleanup systematically varied the seriousness of the spill, the amount of technical information provided in the story, and the agency behavior and resulting community outrage. The outrage manipulation significantly affected affective and cognitive components of perceived risk, but not hypothetical behavioral intentions. Seriousness and technical detail had very little effect on perceived risk.     

Foodborne Exposure to Pesticides and Methylmercury in the United Arab Emirates

As part of a comprehensive environmental health strategic planning project initiated by the government of Abu Dhabi, we assessed potential dietary exposure in the United Arab Emirates (UAE) to methylmercury (in seafood) and pesticides (in fruits and vegetables) above international guideline levels. We present results for the UAE population by age, gender, and body mass index. Our results show very low daily risks of exposure to pesticides in fruits and vegetables at levels exceeding WHO guidelines even under the conservative assumption that no pesticides are removed during washing and food preparation. Thus, exposure to pesticides on fruits and vegetables does not appear to be a major public health concern in the UAE. The chances of exposure to methylmercury in seafood are much higher; our model estimates a mean 1 in 5 daily risk of exceeding the FAO/WHO provisional tolerable weekly intake. However, great caution should be used in interpreting these results, as we analyzed only the risks and not the substantial benefits of fish consumption. In fact, previous studies have demonstrated that exposure to the n‐3 polyunsaturated fatty acids in fish can increase IQ in developing children, and it can substantially decrease the risk in adults of coronary heart disease and stroke. Further research is warranted to compare the risk of Me‐Hg exposure from fish to the nutritional benefits of fish consumption in the UAE and to determine appropriate methods to communicate risk and benefit information to the UAE population.     

Determinants and Mapping of Collective Perceptions of Technological Risk: The Case of the Second Nuclear Power Plant in Taiwan

Nuclear power is a highly controversial and salient example of environmental risk. The siting or operating of a nuclear power plant often faces widespread public opposition. Although studies of public perceptions of nuclear power date back to 1970s, little research attempts to explain the spatial heterogeneity of risk attitude toward nuclear power among individuals or communities. This article intends to improve the knowledge about the major factors contributing to nuclear power plant risk perceptions by mapping the geographical patterns of local risk perception and examining the determinants in forming the nature and distribution of the perceived risk among potentially affected population. The analysis was conducted by a case study of the Second Nuclear Power Plant (SNPP) in Taiwan by using a novel methodology that incorporates a comprehensive risk perception (CRP) model into an ethnographic approach called risk perception mapping (RPM). First, we examined the determinants of local nuclear power risk perceptions through the CRP model and multivariate regression analysis. Second, the results were integrated with the RPM approach to map and explain the spatial pattern of risk perceptions. The findings demonstrate that the respondents regard the nuclear power plant as an extremely high‐risk facility, causing them to oppose the SNPP and reject the compensation payment to accept its continuing operation. Results also indicate that perceptions of nuclear power risk were mainly influenced by social trust, psychological and socioeconomic attributes, proximity, and the perceived effects of the SNPP on the quality of everyday life.     

Risk Perception and Risk Talk: The Case of the Fukushima Daiichi Nuclear Radiation Risk

Individuals’ perceptions and their interpersonal communication about a risk event, or risk talk, can play a significant role in the formation of societal responses to the risk event. As they formulate their risk opinions and speak to others, risk information can circulate through their social networks and contribute to the construction of their risk information environment. In the present study, Japanese citizens’ risk perception and risk talk were examined in the context of the Fukushima Daiichi nuclear radiation risk. We hypothesized and found that the risk information environment and risk literacy (i.e., competencies to understand and use risk information) interact to influence their risk perception and risk talk. In particular, risk literacy tends to stabilize people's risk perceptions and their risk communications. Nevertheless, there were some subtle differences between risk perception and communication, suggesting the importance of further examination of interpersonal risk communication and its role in the societal responses to risk events.     

Conventional Wisdom on Risk Communication and Evidence from a Field Experiment

A recent comprehensive review of the literature identified a number of facts and principles governing risk communication. This paper evaluates several of these propositions using recent evidence from a field experiment in communicating the risks from radon in homes. At this point in the research, data relates primarily to the response of risk perceptions to different information treatments and different personal characteristics. The effect of various causal factors is sensitive to the particular test of risk perception applied. No information treatment was clearly superior for all tasks. An important implication of these findings is that risk communicators must determine what specific task or tasks the information program should enable people to do.     

Evaluating Risk Communication: Examining Target Audience Perceptions About Four Presentation Formats for Fish Consumption Health Advisory Information

Information format can influence the extent to which target audiences understand and respond to risk-related information. This study examined four elements of risk information presentation format. Using printed materials, we examined target audience perceptions about: (a) reading level; (b) use of diagrams vs. text; (c) commanding versus cajoling tone; and (d) use of qualitative vs. quantitative information presented in a risk ladder. We used the risk communication topic of human health concerns related to eating noncommercial Great Lakes fish affected by chemical contaminants. Results from the comparisons of specific communication formats indicated that multiple formats are required to meet the needs of a significant percent of anglers for three of the four format types examined. Advisory text should be reviewed to ensure the reading level is geared to abilities of the target audience. For many audiences, a combination of qualitative and quantitative information, and a combination of diagrams and text may be most effective. For most audiences, a cajoling rather than commanding tone better provides them with the information they need to make a decision about fish consumption. Segmenting audiences regarding information needs and communication formats may help clarify which approaches to take with each audience.     

The Determinants of Trust and Credibility in Environmental Risk Communication: An Empirical Study

This study examines a key component of environmental risk communication; trust and credibility. The study was conducted in two parts. In the first part, six hypotheses regarding the perceptions and determinants of trust and credibility were tested against survey data. The hypotheses were supported by the data. The most important hypothesis was that perceptions of trust and credibility are dependent on three factors: perceptions of knowledge and expertise; perceptions of openness and honesty; and perceptions of concern and care. In the second part, models were constructed with perceptions of trust and credibility as the dependent variable. The goal was to examine the data for findings with direct policy implications. One such finding was that defying a negative stereotype is key to improving perceptions of trust and credibility.     

The Nevada Initiative: A Risk Communication Fiasco

The U.S. Congress has designated Yucca Mountain, Nevada as the only potential site to be studied for the nation's first high-level nuclear waste repository. People in Nevada strongly oppose the program, managed by the U.S. Department of Energy. Survey research shows that the public believes there are great risks from a repository program, in contrast to a majority of scientists who feel the risks are acceptably small. Delays in the repository program resulting in part from public opposition in Nevada have concerned the nuclear power industry, which collects the fees for the federal repository program and believes it needs the repository as a final disposal facility for its high-level nuclear wastes. To assist the repository program, the American Nuclear Energy Council (ANEC), an industry group, sponsored a massive advertising campaign in Nevada. The campaign attempted to assure people that the risks of a repository were small and that the repository studies should proceed. The campaign failed because its managers misunderstood the issues underlying the controversy, attempted a covert manipulation of public opinion that was revealed, and most importantly, lacked the public trust that was necessary to communicate credibly about the risks of a nuclear waste facility.     

Does Communicating (Flood) Risk Affect (Flood) Risk Perceptions? Results of a Quasi‐Experimental Study

People's risk perceptions are generally regarded as an important determinant of their decisions to adjust to natural hazards. However, few studies have evaluated how risk communication programs affect these risk perceptions. This study evaluates the effects of a small-scale flood risk communication program in the Netherlands, consisting of workshops and focus group discussions. The effects on the workshop participants' ( n  = 24) and focus group participants' ( n  = 16) flood risk perceptions were evaluated in a pretest-posttest control group ( n  = 40) design that focused on two mechanisms of attitude change—direct personal experience and attitude polarization. We expected that (H1) workshop participants would show greater shifts in their flood risk perceptions compared with control group participants and that (H2) focus groups would rather produce the conditions for attitude polarization (shifts toward more extreme attitudinal positions after group discussion). However, the results provide only modest support for these hypotheses, perhaps because of a mismatch between the sessions' contents and the risk perception measures. An important contribution of this study is that it examined risk perception data by both conventional tests of the mean differences and tests for attitude polarization. Moreover, the possibility that attitude polarization could cause people to confirm their preexisting (hazard) beliefs could have important implications for risk communication.     

Assessing the Effects of Information About Global Population Growth on Risk Perceptions and Support for Mitigation and Prevention Strategies

The human population is forecast to increase by 3–4 billion people during this century and many scientists have expressed concerns that this could increase the likelihood of certain adverse events (e.g., climate change and resource shortages). Recent research shows that these concerns are mirrored in public risk perceptions and that these perceptions correlate with a willingness to adopt mitigation behaviors (e.g., reduce resource consumption) and preventative actions (e.g., support actions to limit growth). However, little research has assessed the factors that influence risk perceptions of global population growth (GPG). To contribute to this important goal, this article presents three studies that examined how risk perceptions of GPG might be influenced by textual‐visual representations (like those in media and Internet articles) of the potential effects of GPG. Study 1 found that a textual narrative that highlighted the potential negative (cf. positive) consequences of GPG led to higher perceived risk and greater willingness to adopt mitigation behaviors, but not to support preventative actions. Notably, the influence of the narratives on perceived risk was largely moderated by the participant's prior knowledge and perceptions of GPG. Contrary to expectations, studies 2 and 3 revealed, respectively, that photographs depicting GPG‐related imagery and graphs depicting GPG rates had no significant effect on the perceived risk of GPG or the willingness to embrace mitigation or preventative actions. However, study 3 found that individuals with higher “graph literacy” perceived GPG as a higher risk and were more willing to adopt mitigation behaviors and support preventative actions.     

Preventive Health Behavior and Adaptive Accuracy of Risk Perceptions

This study examined the relation between health behavior and risk perceptions in the context of an acute livestock epidemic. Participants in a longitudinal web-based survey ( N = 195) were asked to report their meat consumption and their perceived risk in relation to bovine spongiform encephalopathy (BSE) and other related livestock diseases. Cross-sectional analyses at both measurement points (T1 and T2) showed that participants with low levels of preventive nutrition (high meat consumption) felt more at risk for BSE-related diseases than those reporting comparable higher levels of preventive behavior (low meat consumption), indicating relative accuracy. These results suggest that people recognize when their behavior is risky. More importantly, perceived risk also showed adaptive accuracy from a change perspective: increases in preventive nutrition from T1 to T2 were significantly associated with decreases in perceived risk between T1 and T2. Possible foundations and implications of an adaptive accuracy of risk perceptions are discussed.     

The Role of Emotions in Risk Communication

We present two experiments investigating the role of emotions concerning technological and natural hazards. In the first experiment, technological hazards aroused stronger emotions, and were considered to be riskier than natural hazards. No differences were found between the texts versus audio presentations. However, the presence of pictures aroused stronger emotions and increased the perceived risk. Emotions play a mediating role between hazard types and perceived risk, as well as between pictures and perceived risk. The second experiment adopted real‐world materials from webpages and TV. Emotions again play a mediating role between pictorial information and risk perception. Moreover, specific emotions were found to be associated with different types of action tendencies. For example, loss‐based emotions (e.g., fear, regret) tend to lead to prevention strategies, whereas ethical emotions (e.g., anger) lead to aggressive behavior. We also find that loss‐based emotions in the technical hazard scenario trigger more coping strategies (from prevention to retaliation) than in the natural hazard scenario.     

Improving Risk Communication in Government: Research Priorities

Despite the increased interest in risk communication among government agencies, there is evidence that agencies'risk communication practices lag. We conducted a study to explore which risk communication research would be most important to improve government agencies'risk communication practices. Qualitative interviews and a survey of 145 risk communication experts based in academic institutions and government agencies explored how important research on each of 48 topics would be to improving agencies'risk communication efforts. Respondents identified topics within three areas as priorities for further research: 1) involving communities in agency decisionmaking; 2) communicating with communities of different races, ethnic backgrounds, and incomes; and 3) evaluating risk communication. Both practitioners and researchers responded to additional statements about agencies'risk communication practices with reservations about staff and managers'commitment to effective communication about environmental issues. We discuss the implications of these findings.     

Dead Reckoning: Demographic Determinants of the Accuracy of Mortality Risk Perceptions

General patterns of bias in risk beliefs are well established in the literature, but much less is known about how these biases vary across the population. Using a sample of almost 500 people, the regression analysis in this article yields results consistent with the well-established pattern that small risks are overassessed and large risks are underassessed. The accuracy of these risk beliefs varies across demographic factors, as does the switch point at which people go from underassessment to overassessment, which we found to be 1500 deaths annually for the full sample. Better educated people have more accurate risk beliefs, and there are important differences in the risk perception by race and gender that also may be of policy interest.     

Communicating Conservation Status: How Different Statistical Assessment Criteria Affect Perceptions of Extinction Risk

Although alternative forms of statistical and verbal information are routinely used to convey species’ extinction risk to policymakers and the public, little is known about their effects on audience information processing and risk perceptions. To address this gap in literature, we report on an experiment that was designed to explore how perceptions of extinction risk differ as a function of five different assessment benchmarks (Criteria A–E) used by scientists to classify species within IUCN Red List risk levels (e.g., Critically Endangered, Vulnerable), as well as the role of key individual differences in these effects (e.g., rational and experiential thinking styles, environmental concern). Despite their normative equivalence within the IUCN classification system, results revealed divergent effects of specific assessment criteria: on average, describing extinction risk in terms of proportional population decline over time (Criterion A) and number of remaining individuals (Criterion D) evoked the highest level of perceived risk, whereas the single‐event probability of a species becoming extinct (Criterion E) engendered the least perceived risk. Furthermore, participants scoring high in rationality (analytic thinking) were less prone to exhibit these biases compared to those low in rationality. Our findings suggest that despite their equivalence in the eyes of scientific experts, IUCN criteria are indeed capable of engendering different levels of risk perception among lay audiences, effects that carry direct and important implications for those tasked with communicating about conservation status to diverse publics.