Risk Communication and Attitude Change: Taiwan's Experience

Many analysts and policymakers now appreciate that environmental problems are unlikely to be eliminated with some technological fix. Instead, they are beginning to describe environmental goals in terms of risk management. With this reorientation comes a growing recognition of the disparity between experts' assessment and the public's perception of what constitutes serious risks. This disparity is particularly evident for the risks posed by hazardous and nuclear materials.

During the 1980s several surveys of peoples' attitudes toward different land uses revealed that facilities for producing, using, or disposing of nuclear or hazardous substances were considered the least desirable land use. People surveyed in different countries consistently rated nuclear power plants or nuclear waste disposal sites as the most serious among a number of sources of risks. In spite of these surveys, many scientists remain convinced that if people are given the facts, their perception of the risks posed by hazardous substances will begin to align with scientific judgments about these risks. However, the results of a nationwide effort in Taiwan to disseminate the facts about nuclear power plants suggests that this convergence of public perception and expert assessment is unlikely to occur.

In December 1984, Taiwan's state-operated power corporation, Taipower, announced plans for the nation's fourth power plant, to be constructed on the northeastern coast of Taiwan. In Taiwan public concern over the safety of nuclear power had been heightened by the Three Mile Island accident in the United States. The accident raised interest in and public awareness of the safety records of the three existing nuclear plants in Taiwan. (The record of leaks and shutdowns for these Taiwanese plants has not been good by U.S. standards. From 1984 to 1988, the radiation leaks in each plant were substantial, averaging more than twenty per year at two of the three plants.) The Soviet Union's Chernobyl accident in 1986 also increased concern about the proposed fourth plant.

Because Taipower had agreed to delay planning another nuclear power plant until it established a greater degree of public consensus on the plant's merits, the company sought to change public attitudes about the safety of nuclear power by organizing a national debate on the safety of nuclear power and the need for a fourth plant. A national risk communication program on nuclear power and the proposed plant was announced in February 1989. A budget of more than $460,000 was allocated to the program. The program included one hundred debates and discussion-group sessions at universities and cultural centers in Taiwan's major cities, fifty lectures on the safety of and need for the proposed plant at high schools and cultural centers in these same cities, and a series of television programs and articles in local newspapers that emphasized the merits of the fourth plant. In addition, Taipower announced a program that would provide a fund of more than $6 million per year for compensating people residing near the proposed facility during the ten-year construction period, and another $4.6 million per year for compensation after the plant begins operation.

Two surveys of 404 households in Taiwan—one made in March 1988 (before the nuclear power debates) and one made in July 1989 (after the debates)—provide evidence about how attitudes toward the proposed plant have changed as a result of Taipower's risk communication initiative. Analysis of the surveys suggests that, in general, the debates increased respondents' perception of the seriousness of risks from the proposed plant.

Peoples' perception of risks can be influenced by experience. In fact, the influence of experience on perceptions is an important element in a rational theory of behavior given uncertainty about risks. One of the most successful empirical risk perception models describes how people use information to update their initial perception of risk. The model maintains that current risk perceptions, usually elicited using a simple index, are a weighted average of a person's perceptions prior to receiving new information combined with his or her understanding of this information. The message that a person receives about risk from new information may be different than that intended by the information.

Most of the existing applications of this model involve one of two types of situations. The first consists of interviews in which individuals are asked about their risk perceptions, given information about a hypothetical situation that could affect their risk, and then asked what their new perceptions of risk would be for that situation. While this approach is consistent with the basic framework of the empirical risk perception model, it does not represent a strong test of the process by which people update their risk perceptions. Because each interview lasts a short period of time (usually less than one hour for personal interviews and twenty minutes or less for telephone interviews), the model must assume that responses to new information given within the space of the interview offer a reasonable description of how people would respond to new information over the longer periods of time usually available for actual decisions.

The second type of application of the empirical risk peception model overcomes this limitation. This type was used in a study of how 2,300 homeowners in the state of New York who had their homes monitored for radon (an indoor air pollutant considered to be a serious source of lung cancer risk) updated their risk perceptions as they received new information about radon readings for their homes and about the health risks of radon. The study was designed to control the information study participants received about risks associated with radon and to observe each person's reaction to new radon readings over nearly a twenty-month period.

Two aspects of the study's findings are especially relevant to how perceptions of risks associated with nuclear power plants changed in Taiwan. First, like the Taiwan study, the New York study found that prior beliefs were important in each participant's current perception of risk. The application of an empirical risk perception model in the New York study confirmed that as individuals updated their initial perception of risk with progressively refined information about radon levels in their homes, the weight they attached to their prior perceptions of risk increased about sevenfold.

Second, the information explaining how to interpret radon readings in quantitative terms was found to be influential in participants' first update of their perception of risk, but not generally influential when supplementary radon readings were received over a longer time span and for different parts of each person's home. However, to the extent that this information encouraged people to think in terms of radon thresholds—that is, a reading below a specified radon exposure level would indicate an acceptable level of risk, and one above it would indicate an unacceptable level—this framing did appear to affect how people responded to new readings that exceeded the threshold.

These findings suggest that the estimated parameters of models for describing how people use new information to update risks over time may provide approximate gauges of the confidence people place on their prior perceptions. Empirical risk perception models therefore offer the potential for evaluating whether programs to disseminate information about risk induce changes in the public's perception of risk.

Impact of Taiwan's nuclear power debates

To evaluate the impact of the nuclear power debate in Taiwan on the public's perception of risks from a proposed nuclear power plant, researchers from the Institute of Economics at Academia Sincia (Taiwan) and North Carolina State University employed empirical risk perception models to analyze changes in attitude indicated by responses to the pre-and post-debate surveys mentioned above. The first survey, sponsored by the government of Taiwan in March 1988, elicited attitudes toward the proposed plant through personal interviews with 2,001 households in two cities and two counties in Taiwan. Using a mail questionnaire, the researchers conducted a second survey of these same households in July and August 1989. Of the households participating in the personal interview, 22.6 percent responded to the mail survey. Of the 404 households that returned the mail survey, 286 responded to a question (first asked in the personal interview) that solicited a rating of the risk from nuclear power plants in Taiwan, and 398 provided sufficiently complete information on their attitudes toward the proposed power plant to describe how these attitudes changed.

Risk communication efforts usually serve one or more of four objectives: conveying information to and educating the public, encouraging change in behavior and protective action, warning the public about potential disasters or emergencies, and facilitating the solution of problems and the resolution of conflicts. Taipower's national debate on nuclear power sought to inform people about the experts' appraisal of the risks posed by nuclear power plants and to resolve conflicts about the efficacy of a proposed plant. Analysis of the surveys in which 404 households in Taiwan participated suggests that the debate was not effective in attaining the latter goal.

The nuclear power debate in Taiwan highlights the difficulty of treating risk management as a two-way process between experts and the public when the intention is to ensure public acceptance of the experts' judgments concerning risk. However, inferences drawn from that debate for other risk communication efforts should be limited. Clearly, the design of a risk communication program is an important factor in its success, as is the source of risk it addresses. Equally important is the degree to which citizens believe they have access to some governmental entity, such as the courts, that can evaluate administrative rulemaking and decisionmaking. These and other factors must be considered in assessing how the findings on Taiwan's national debate on nuclear power contribute to our understanding of the potential for risk communication efforts to narrow the gap between the public's perception and experts' judgments about various risks.