CHAPTER THREE e erceivin g Risks Both risks and benefits have to be considered when seeking to understand what drives some behaviours and why some interventions are more acceptable and successful than others. Social, cultural and economic factors are central to how individuals perceive health risks. Similarly, societal and structural factors can influence which risk control policies are adopted and the impact that interventions can achieve. Preventing risk factors has to be planned within the contert of local society, bearing in mind that the success ofpreventive interventions is only partly a matter of individual circumstances and education. In designing intervention strategies, it cannot automatically be assumed that the diverse groups which make up the general public think in the same way as public health professionals and other risk experts. In addition, estimates of risk and its consequences, presented in scientific terms based on a risk assessment, have to be communicated with particular caution and care. The best way is for well- respected professionals, who are seen to be independent and credible, to make the communications. An atmosphere of trust between the government and all interested parties, in both thepublicand private sectors, is essential ifinterventions are to be adopted and successfully implemented
Perceiving Risks 27 CHAPTER THREE erceiving isks 27 Both risks and benefits have to be considered when seeking to understand what drives some behaviours and why some interventions are more acceptable and successful than others. Social, cultural and economic factors are central to how individuals perceive health risks. Similarly, societal and structural factors can influence which risk control policies are adopted and the impact that interventions can achieve. Preventing risk factors has to be planned within the context of local society, bearing in mind that the success of preventive interventions is only partly a matter of individual circumstances and education. In designing intervention strategies, it cannot automatically be assumed that the diverse groups which make up the general public think in the same way as public health professionals and other risk experts. In addition, estimates of risk and its consequences, presented in scientific terms based on a risk assessment, have to be communicated with particular caution and care. The best way is for wellrespected professionals, who are seen to be independent and credible, to make the communications. An atmosphere of trust between the government and all interested parties, in both the public and private sectors, is essential if interventions are to be adopted and successfully implemented.
PERCEIVING RISKS CHANGING PERCEPTIONS OF RISK iven the research on the global burden of risks to health, together with the analysi that underpins the choice of cost-effective interventions, what lessons have been learned about risk perceptions? For high priority risks, how can we implement more effective risk avoidance and reduction policies in the future? This chapter starts with an overview of how the study of risk analysis has developed since the 1970s. It then draws attention to the need to have a broad perspective on how risks are defined and perceived in society, both by individuals and by different groups. Next, emphasis is given to the importance of improving communications about health risks if successful strategies are to be adopted to control them. However, risk perceptions all over the world are increasingly being influenced by three other trends. First, by the power and influence of special interest groups connected to corporate business interests and the opposition being organized by many advocacy and public health groups. Second, by the increasing influence of the global mass media. And third, by the increase in risk factors within many middle and low income countries as a consequence of the effects of globalization Until recently, risks to health were defined largely from the scientific perspective, even ough it has been recognized for some time that risks are commonly understood and interpreted very differently by different groups in society, such as scientists, professionals, and politicians. Assessment and management of risks to health is a relatively new area of study that has been expanding steadily since the early 1970s.It began by focusing on developing scientific methods for identifying and describing hazards and for assessing the probability of associated adverse outcome events and their onsequences. Particular attention has been given to the type and scale of the adverse consequences, including any likely mortality. In the early years, risk analysis, as it was the called, was seen mainly as a new scientific activity concerned with environmental and other external threats to health, such as chemical exposures, road traffic accidents, and radiation and nuclear power disasters. The early study of risk developed mainly in the USA and During the early 1980s, risk analysis evolved into the two main phases of risk assessment and risk management, as more attention was given to how hazards or risk factors could be controlled at both the individual level and by society as a whole. The emphasis moved from determining the probability of adverse events for different risk factors to assessing the scale
Perceiving Risks 29 CHANGING PERCEPTIONS OF RISK iven the research on the global burden of risks to health, together with the analysis that underpins the choice of cost-effective interventions, what lessons have been learned about risk perceptions? For high priority risks, how can we implement more effective risk avoidance and reduction policies in the future? This chapter starts with an overview of how the study of risk analysis has developed since the 1970s. It then draws attention to the need to have a broad perspective on how risks are defined and perceived in society, both by individuals and by different groups. Next, emphasis is given to the importance of improving communications about health risks if successful strategies are to be adopted to control them. However, risk perceptions all over the world are increasingly being influenced by three other trends. First, by the power and influence of special interest groups connected to corporate business interests and the opposition being organized by many advocacy and public health groups. Second, by the increasing influence of the global mass media. And third, by the increase in risk factors within many middle and low income countries as a consequence of the effects of globalization. Until recently, risks to health were defined largely from the scientific perspective, even though it has been recognized for some time that risks are commonly understood and interpreted very differently by different groups in society, such as scientists, professionals, managers, the general public and politicians. Assessment and management of risks to health is a relatively new area of study that has been expanding steadily since the early 1970s. It began by focusing on developing scientific methods for identifying and describing hazards and for assessing the probability of associated adverse outcome events and their consequences. Particular attention has been given to the type and scale of the adverse consequences, including any likely mortality. In the early years, risk analysis, as it was then called, was seen mainly as a new scientific activity concerned with environmental and other external threats to health, such as chemical exposures, road traffic accidents, and radiation and nuclear power disasters. The early study of risk developed mainly in the USA and Europe (1). During the early 1980s, risk analysis evolved into the two main phases of risk assessment and risk management, as more attention was given to how hazards or risk factors could be controlled at both the individual level and by society as a whole. The emphasis moved from determining the probability of adverse events for different risk factors to assessing the scale 3 PERCEIVING RISKS
The World Health Report 2002 and range of possible consequences. Deaths are commonly seen as one of the most important consequences. Attempts were also made to reduce any uncertainties in making the scientific estimates(2). An important consequence of this change was that individual people were now seen as being mainly responsibility for handling their own risks to health, since many risks were characterized as behavioural in origin and, therefore, largely under individual control. This in turn led to the lifestyles approach in health promotion. For instance, a great deal of attention was paid to combating coronary heart disease through health promotion aimed at high-risk individuals, such as increasing exercise and lowering dietary cholesterol, while policies for combating cigarette smoking also emphasized the importance of individual The need for stronger government regulatory controls also became more apparent, with two other important developments. First, governments in many industrialized countries saw their role as law enforcers and passed legislation to establish new and powerful publ regulatory agencies, such as the Food and Drug Administration(FDA)in the USA and the Health and Safety Executive(HSE)in the United Kingdom. Second, increased attention was given to deriving minimum acceptable exposure levels and the adoption of many new international safety standards, particularly for environmental and chemical risks. This included, for example, risks associated with air pollutants, vehicle emissions, foods and the QUESTIONING THE SCIENCE IN RISK ASSESSMENT The so-called scientifico quantitative approach to health risk assessment aims to produce the best possible numerical estimates of the chance or probability of adverse health outcomes for use in policy-making. Although high credibility is usually given to this approach, how valid is this assumption? Why is this approach often seen as more valid than the judgements made by the public or social scientists? Although risk assessment appears to follow a scientifically logical sequence, in practice there are considerable difficulties in making"objective "decisions at each step in the calculations. Thus the risk modeller has to adopt a specific definition of risk and needs to introduce into the model a series of more subjective judgements and assumptions(3, 4) lany of these include implicit and subjective values, such as the numerical expression fo risk, weighting the value of life at different ages, the discount rates and choice of adverse ealth outcomes to be included. For instance, scientific judgements may be needed on the effects of different levels of exposure or which outcomes to include, particularly which disease episodes should be counted among the adverse events During the 1980s, scientific predictions were seen to be rational, objective and valid, while public perceptions were believed to be largely subjective, ill-informed and, therefore, less valid. This led to risk control policies that attempted to"correct"and"educate"the public in the more valid scientific notions of risk and risk management. However, this approach was increasingly challenged by public interest and pressure groups, which asked scientists to explain their methods and assumptions.These critical challenges often revealed the high levels of scientific uncertainty that were inherent in many calculations. Such groups then became more confident, enabling them to argue strongly for the validity of their own ents and interpretation of risks
30 The World Health Report 2002 and range of possible consequences. Deaths are commonly seen as one of the most important consequences. Attempts were also made to reduce any uncertainties in making the scientific estimates (2). An important consequence of this change was that individual people were now seen as being mainly responsibility for handling their own risks to health, since many risks were characterized as behavioural in origin and, therefore, largely under individual control. This in turn led to the lifestyles approach in health promotion. For instance, a great deal of attention was paid to combating coronary heart disease through health promotion aimed at high-risk individuals, such as increasing exercise and lowering dietary cholesterol, while policies for combating cigarette smoking also emphasized the importance of individual choice. The need for stronger government regulatory controls also became more apparent, with two other important developments. First, governments in many industrialized countries saw their role as law enforcers and passed legislation to establish new and powerful public regulatory agencies, such as the Food and Drug Administration (FDA) in the USA and the Health and Safety Executive (HSE) in the United Kingdom. Second, increased attention was given to deriving minimum acceptable exposure levels and the adoption of many new international safety standards, particularly for environmental and chemical risks. This included, for example, risks associated with air pollutants, vehicle emissions, foods and the use of agricultural chemicals. QUESTIONING THE SCIENCE IN RISK ASSESSMENT The so-called scientific or quantitative approach to health risk assessment aims to produce the best possible numerical estimates of the chance or probability of adverse health outcomes for use in policy-making. Although high credibility is usually given to this approach, how valid is this assumption? Why is this approach often seen as more valid than the judgements made by the public or social scientists? Although risk assessment appears to follow a scientifically logical sequence, in practice there are considerable difficulties in making “objective” decisions at each step in the calculations. Thus the risk modeller has to adopt a specific definition of risk and needs to introduce into the model a series of more subjective judgements and assumptions (3, 4). Many of these include implicit and subjective values, such as the numerical expression for risk, weighting the value of life at different ages, the discount rates and choice of adverse health outcomes to be included. For instance, scientific judgements may be needed on the effects of different levels of exposure or which outcomes to include, particularly which disease episodes should be counted among the adverse events. During the 1980s, scientific predictions were seen to be rational, objective and valid, while public perceptions were believed to be largely subjective, ill-informed and, therefore, less valid. This led to risk control policies that attempted to “correct” and “educate” the public in the more valid scientific notions of risk and risk management. However, this approach was increasingly challenged by public interest and pressure groups, which asked scientists to explain their methods and assumptions. These critical challenges often revealed the high levels of scientific uncertainty that were inherent in many calculations. Such groups then became more confident, enabling them to argue strongly for the validity of their own assessments and interpretation of risks
Perceiving Risks EMERGING IMPORTANCE OF RISK PERCEPTIONS By the early 1990s, particularly in North America and Europe, it became apparent that relying mainly on the scientific approaches to risk assessment and management was not always achieving the expected results. It also became clear that risk had different meanings to different groups of people and that all risks had to be understood within the larger social cultural and economic context (5-7). In addition, people compare health risks with any associated benefits and they are also aware of a wide array of other relevant risks. In fact, it has been argued that concepts of risk are actually embedded within societies and their cultures, which largely determines how individuals perceive risks and the autonomy they may have to control them(8). In addition, it became apparent that public perceptions of risks to health did not necessarily agree with those of the scientists, whose authority was increasingly being questioned by both the general public and politicians. Although there was considerable agreement between the public and scientists on many risk assessments, there were also some, such as nuclear power and pesticides, where there were large differences of opinion(see Box 3. 1). These differences of perception often led to intense public controvers At the same time, there was also increasing disillusionment with the"lifestyles"approach to health promotion and education strategies, that relied on improving the health knowledge and beliefs of individuals. These approaches were not achieving sufficient behavioural change for the interventions to be judged cost-effective. For instance, the rapid emergence of HIv AIdS demonstrated that relying on the health beliefs model for behavioural change was largely ineffective in reducing the high-risk sexual behaviours that increased transmission in the epidemic. In addition, as the general public and special interest groups, particularly those in the environmental movements, became better organized they also began ao) gng the motives of the large corporate businesses, such as the tobacco industry challe By the mid-1990s, improving risk communications was seen as essential for resolving the differences between these various positions, as it became more widely accepted that both the scientific approaches and public perceptions of risk were valid. It was also generally accepted that differences in perceptions of risk had to be understood and resolved. This in turn led to the conclusion that governments and politicians had a major role to play in handling conflicts over risk policies by promoting open and transparent dialogue within society, in order to have high levels of public trust in such dialogue. A very important lesson is that high levels of trust between all parties are essential if reductions in the future globa burden of risks to health are to be achieved(11, 12) Box 3. 1 Perceptions of risk by scientists and the general public "Perhaps the most important message from sation of risk is much richer than that of experts two-way process. Each side, expert and publi research is that there is wisdom as well as and reflects legitimate concerns that are typically has something valid to contribute. Each side error in public attitudes and perceptions. Lay omitted from expert risk assessments. As a result, must respect the insights and intelligence of the people sometimes lack certain information risk communication and risk management efforts other about hazards. However, their basic conceptuali- are destined to fail unless they are structured as a Source: (9).p. 285
Perceiving Risks 31 EMERGING IMPORTANCE OF RISK PERCEPTIONS By the early 1990s, particularly in North America and Europe, it became apparent that relying mainly on the scientific approaches to risk assessment and management was not always achieving the expected results. It also became clear that risk had different meanings to different groups of people and that all risks had to be understood within the larger social, cultural and economic context (5–7). In addition, people compare health risks with any associated benefits and they are also aware of a wide array of other relevant risks. In fact, it has been argued that concepts of risk are actually embedded within societies and their cultures, which largely determines how individuals perceive risks and the autonomy they may have to control them (8). In addition, it became apparent that public perceptions of risks to health did not necessarily agree with those of the scientists, whose authority was increasingly being questioned by both the general public and politicians. Although there was considerable agreement between the public and scientists on many risk assessments, there were also some, such as nuclear power and pesticides, where there were large differences of opinion (see Box 3.1). These differences of perception often led to intense public controversy. At the same time, there was also increasing disillusionment with the “lifestyles” approach to health promotion and education strategies, that relied on improving the health knowledge and beliefs of individuals. These approaches were not achieving sufficient behavioural change for the interventions to be judged cost-effective. For instance, the rapid emergence of HIV/ AIDS demonstrated that relying on the health beliefs model for behavioural change was largely ineffective in reducing the high-risk sexual behaviours that increased transmission in the epidemic. In addition, as the general public and special interest groups, particularly those in the environmental movements, became better organized they also began challenging the motives of the large corporate businesses, such as the tobacco industry (10). By the mid-1990s, improving risk communications was seen as essential for resolving the differences between these various positions, as it became more widely accepted that both the scientific approaches and public perceptions of risk were valid. It was also generally accepted that differences in perceptions of risk had to be understood and resolved. This in turn led to the conclusion that governments and politicians had a major role to play in handling conflicts over risk policies by promoting open and transparent dialogue within society, in order to have high levels of public trust in such dialogue. A very important lesson is that high levels of trust between all parties are essential if reductions in the future global burden of risks to health are to be achieved (11, 12). Box 3.1 Perceptions of risk by scientists and the general public “Perhaps the most important message from this research is that there is wisdom as well as error in public attitudes and perceptions. Lay people sometimes lack certain information about hazards. However, their basic conceptualisation of risk is much richer than that of experts and reflects legitimate concerns that are typically omitted from expert risk assessments. As a result, risk communication and risk management efforts are destined to fail unless they are structured as a two-way process. Each side, expert and public, has something valid to contribute. Each side must respect the insights and intelligence of the other.” Source: (9). p.285
The World Health Report 2002 RISK PERCEPTIONS The assumption made in this report is that risk factors, risk probabilities and adverse events can be defined and measured. This is a valid starting point for the quantification of the adverse effects of a range of risk factors and for health advocacy. However, as we have seen above, when interpreting the global burden of risks to health and using this to design intervention strategies, wider perspectives are needed. Evaluating these risks must take lace within a much broader context. People's risk perceptions are based on a diverse array of information that they have processed on risk factors(sometimes called hazards) and technologies, as well as on their benefits and contexts. For instance, people receive information and form their values based on their past experience, communications from scientific sources and the media, as well as from family, peers and other familiar groups. This transfer and learning from experience also occurs within the context of a persons society and culture, including references to beliefs and systems of meaning. It is through the organization of all this knowledge, starting in early childhood, that individuals perceive and make sense of their world. In a similar way, perceptions of risks to health are embedded within different economic, social and cultural environments Much of the original impetus for research on perceptions came from the pioneering work of Starr (13)in trying to weigh the risks from technologies against their perceived benefits. Empirical studies of individual risk perceptions had their origins mainly in psychological studies conducted in the USA (4, 14). A major early discovery was of a set of mental strategies orrules, also called heuristics, that people use to understand risks(15).An arly approach to study and map people s understanding of risks was to ask them to estimate the number of deaths for 40 different hazards and to compare these with known statistical estimates(16, 17). This showed that people tend to overestimate the number of deaths from rarer and infrequent risks, while underestimating considerably those from common and frequent causes, such as cancers and diabetes. This finding has obvious implications for control strategies that are focused on many common and widely distributed risks to health In addition, rare but vivid causes are even more overestimated. Familiarity and exposure through the mass media tend to reinforce these perceptions. However, people' s rank ordering the total number of deaths does usually correspond well overall with the rank order of official estimates Risk factors have many dimensions, including a variety of benefits, and certainly risk means far more to most people than just the possible number of deaths. Another pioneering research study, which is relevant to the present analysis of global risks to health, used psychometric testing to measure perceptions of 90 different hazards using 18 separat alitative characteristics(18). Following factor analysis these hazards were scaled depending on their degree of"dread"and their degree of"unknown risk"(see Figure 3.1, which shows 20 risks selected from the original 90). A third factor(not shown in the figure)related to the number of people involved. Figure 3. 1 clearly shows that the most highly uncertain risks, ch as nuclear power and pesticides, are the most dreaded, whil nany health interventions and clinical procedures have more acceptable values. For instance, e dread factor levels and the higher the perceived unknown risks, the more people want action to reduce these risks, including through stricter government regulation and legislative perceived risks. Rather, they want stronger controls against many nist of benefits against controls. It appears that people often do not make a simple trade-off
32 The World Health Report 2002 RISK PERCEPTIONS The assumption made in this report is that risk factors, risk probabilities and adverse events can be defined and measured. This is a valid starting point for the quantification of the adverse effects of a range of risk factors and for health advocacy. However, as we have seen above, when interpreting the global burden of risks to health and using this to design intervention strategies, wider perspectives are needed. Evaluating these risks must take place within a much broader context. People’s risk perceptions are based on a diverse array of information that they have processed on risk factors (sometimes called hazards) and technologies, as well as on their benefits and contexts. For instance, people receive information and form their values based on their past experience, communications from scientific sources and the media, as well as from family, peers and other familiar groups. This transfer and learning from experience also occurs within the context of a person’s society and culture, including references to beliefs and systems of meaning. It is through the organization of all this knowledge, starting in early childhood, that individuals perceive and make sense of their world. In a similar way, perceptions of risks to health are embedded within different economic, social and cultural environments. Much of the original impetus for research on perceptions came from the pioneering work of Starr (13) in trying to weigh the risks from technologies against their perceived benefits. Empirical studies of individual risk perceptions had their origins mainly in psychological studies conducted in the USA (4, 14). A major early discovery was of a set of mental strategies or rules, also called heuristics, that people use to understand risks (15). An early approach to study and map people’s understanding of risks was to ask them to estimate the number of deaths for 40 different hazards and to compare these with known statistical estimates (16, 17). This showed that people tend to overestimate the number of deaths from rarer and infrequent risks, while underestimating considerably those from common and frequent causes, such as cancers and diabetes. This finding has obvious implications for control strategies that are focused on many common and widely distributed risks to health. In addition, rare but vivid causes are even more overestimated. Familiarity and exposure through the mass media tend to reinforce these perceptions. However, people’s rank ordering by the total number of deaths does usually correspond well overall with the rank order of official estimates. Risk factors have many dimensions, including a variety of benefits, and certainly risk means far more to most people than just the possible number of deaths. Another pioneering research study, which is relevant to the present analysis of global risks to health, used psychometric testing to measure perceptions of 90 different hazards using 18 separate qualitative characteristics (18). Following factor analysis these hazards were scaled depending on their degree of “dread” and their degree of “unknown risk”(see Figure 3.1, which shows 20 risks selected from the original 90). A third factor (not shown in the figure) related to the number of people involved. Figure 3.1 clearly shows that the most highly uncertain risks, such as nuclear power and pesticides, are the most dreaded, while risks associated with many health interventions and clinical procedures have more acceptable values. For instance, antibiotics, anaesthetics, childbirth and surgery are perceived as being much safer. The higher the dread factor levels and the higher the perceived unknown risks, the more people want action to reduce these risks, including through stricter government regulation and legislative controls. It appears that people often do not make a simple trade-off of benefits against perceived risks. Rather, they want stronger controls against many risks