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OCR for page 94
5
Common Misconceptions About
Risk Communication
Some of the more important misconceptions about risk commu-
nication, including unrealistic expectations about what it can accom-
plish, are discussed in this chapter. Once these misconceptions are
dispelled, the real problems of risk communication can be addressed.
We have taken care to distinguish between risk communication
and risk management and between risk communication and risk mes-
sages. The primary goal of risk communication is to inform the par-
ticipants in decisions about risks. Neither successful communication
nor successful execution of the political process guarantees that risk
management decisions will maximize welfare in terms of reducing
exposure to hazards. Yet many people judge risk communication by
the quality of the relevant risk management decisions.
We take political constraints as given and attempt to find ways
within them to inform debates about risk. A well-informed decision
process is likely to yield better decisions than an uninformed process.
If all participants are adequately informed, the ultimate decision is
more likely to improve conditions for all involved than a decision
made by experts alone.
It is important, however, to realize that because risk commu-
nication usually involves multiple messages from many sources, and
because these messages contain difficult and complex ideas, there is
no simple way of making risk communication easy.
Risk messages necessarily compress technical information, which
94
OCR for page 95
COMMON MISCONCEPTIONS ABOUT RISK COMMUNICATION 95
can lead to misunderstanding, confusion, and distrust. Preparing risk
messages can involve choosing between a message that is so extensive
and complex that only experts can understand it and a message that
is more easily understood by nonexperts but that is selective and thus
subject to challenge as being inaccurate or manipulative.
Since it is a reasonable precaution to assume that the compres-
sion in risk messages may introduce intentional or unintentional bias,
it is natural to treat risk messages as reflecting political as well as
scientific elements. Because people view risk messages as incorporat-
ing both scientific and political elements, appeals to scientific quality
and veracity alone on the part of the risk communicator may not
always sway the skeptic.
EXPECTATIONS REGARDING RISE COMMUNICATION
Many peopic including some scientists, decision makers, and
members of the public have unrealistic expectations about what
can be accomplished by risk communication. It is mistaken to expect
improved risk communication to always reduce conflict and smooth
risk management. In addition, risk comparisons alone cannot estab-
lish levels of acceptable risk or ensure systematic minunization of risk,
although they can help people comprehend unfamiliar magnitudes.
Communication, Conflict, and Management
Many people, especially decision makers, seem to think that
well-crafted messages or communication campaigns can eliminate or
reduce conflicts in risk issues. These individuals believe that the
conflicts are based on lack of information, that if all the parties
were made aware of the facts, they would agree. This overlooks the
possibility that conflicts are based on factors such as distribution of
risks and benefits (e.g., do both fall equally on the same people?),
different values (e.g., are the participants risk averse as opposed to
risk seeking?), and different goals (e.g., is it better to avoid food
additives or to enhance preservation and length of storage for food
stuffs?.
Communication may reduce conflict about risks in some in-
stances. However, when the underlying knowledge is uncertain, when
people disagree about the meaning of existing data, when there is
disagreement about the acceptable level of risk-in other words, in
most cases of conflict about risk informative risk messages might
make the issues, and thus the conflict, clearer and more obvious.
OCR for page 96
96
IMPROVING RISK COMMUNICATION
t
In the Introduction we discussed the desire to develop effective
alternatives to regulatory control as one of the reasons for interest
in risk communication. But not all people see this as a positive de-
velopment. The possibility of diverting attention from the risks and
their control with careful information campaigns is sufficient to make
some observers chary of risk communication. Ellen Silbergeld, senior
scientist with the Environmental Defense Fund, expressed ambiva-
lence about the large attendance (approximately 500) at the National
Conference on Risk Communication in 1986. She viewed increased
interest in the topic as a result of the destruction of consensus on en-
vironmental and other risk areas and described risk communication
as a "shield for inaction" (Silbergeld, 1987a).
Comparing Risks
Another mistaken expectation is that risk comparisons can be
used to determine acceptable levels of risk and help minimize overall
exposures. Comparing different risks can help people comprehend the
uncommon magnitudes involved and understand the level, or mag-
nitude, of risk associated with a particular hazard. But comparison
with other risks cannot itself establish the acceptability of the risk
in question. To realize, for example, that the chance of death from a
previously unknown risk is about the same as that from a known risk
does not necessarily imply that the two risks are equally acceptable.
Generally, comparing risks along a single dimension is not helpful
when the risks are widely perceived as qualitatively different.
Risk messages commonly convey quantitative information that
is unfamiliar and difficult to comprehend. These magnitudes and risk
estimates are not easily understood without benchmarks or points
of reference, and providing careful comparisons can help people un-
derstand this information. Risk magnitudes are difficult enough to
understand when referring to a single consequence, such as death.
But comparison of different consequences, such as injury, disability,
or chronic disease, is even more difficult.
An interesting approach is the use of risk ladders, for which a
range of probabilities is presented for a single class of risks. Although
this technique can help people understand the magnitudes, it is not
without problems. Figure 5.1 shows two examples of risk ladders. We
consider the first weaker because of the several deficiencies listed. The
second is considered stronger because it involves fewer deficiencies.
The two risk ladders illustrate both the potential of the approach
and the difficulty of using comparison. (Note: Not all attributes of
OCR for page 97
COMMON MISCONCEPTIONS ABOUT RISK COMMUNICATION 97
the two risk ladders have been empirically tested, so it is not possible
to state with certainty how people will react to them. The principal
weaknesses listed are based on the existing literature. Each practical
use of risk comparison should be carefully pretested if possible.)
Use of multiple comparisons helps counteract the possibility that
people may severely misestimate a particular risk, even though it is
familiar to them. It also reduces the danger of arousing the scien-
tific disputes that can often arise when only two risk estimates are
compared, one or both of which are subject to scientific debate.
One difficulty in risk comparison is that it is often difficult to find
risks that are sufficiently similar to make the comparison meaningful.
The easiest way to avoid comparing apples and oranges is to compare
the risk associated with the same hazard at different times or risks
associated with different options for achieving the same purpose.
These comparisons are the least problematic because they address
the same hazards and consequences with variation in the mechanisms
for controlling or reducing the risk in question.
When such direct comparisons are not possible, it is important to
recognize that various risks have different qualitative characteristics
and that these can affect the way comparisons are viewed (Fischhoff
et al., 1981a; SIovic, 1987; SIovic et al., 1980~. Two that have been
shown to have considerable impact are composite indices derived
from factor analysis. The first, labeled "dread," is associated with
perceived lack of control, dread, catastrophic potential, and fatal
consequences. The second, called "unknown," is associated with the
degree to which the risk is perceived to be unobserved, unknown, new,
and with delayed manifestations of harm (SIovic, 1987~. Hazards
whose quantitative risks are estimated to be the same or sirn~lar may
result in quite different responses if their qualitative characteristics
are sufficiently different. Care must be taken that the risks compared
exhibit qualitative characteristics that are reasonably similar.
Another pitfall of risk comparison is the appearance of selecting
risks for comparison that minimize or otherwise trivialize the risk in
question (Covello et al., 1988~. Compendiums of risks, or risk ladders
placing various risks along a spectrum from Tower to higher, may give
this appearance when the risk in question is much lower than other
risks and when there are few risks presented with comparable levels.
If, however, the comparison presents risks that clearly relate to the
risk in question and relate or position its level or magnitude, the
appearance of trivialization can probably be avoided.
OCR for page 98
98
ANNUAL NUMBER OF DEATHS PER MILLION PEOPLE
Smoking 1 Pack of
Cigarettes per Day [A
Riding a Motorcycle
Fighting a Fire
1
Driving a Car LO
Pedestrian Hit by a Car
Drinking 1 Diet Soda per
Day (Saccharin Based)
Taking X-rays for
Diagnoisis
Being Hit by Lightning
or a Tornado
IMPROVING RISK COMMUNICATION
l
10,000
1,000
100
1
. /
\/
PRINCIPAL WEAKNESSES:
(1) Estimated levels of
risk are presented on a
log scale; some people
will likely fail to
realize that distances
of the same length
between different
points on the scale in
fact represent
different magnitudes.
(2) Ali risks are
presented as point
estimates;
uncertainties are not
indicated.
(3) Periods of exposure
are not defined.
(4) Exposure base is
not defined (total
population or number
exposed), and yet risks
are compared directly.
(5) Risks with very
different qualitative
attributes are
included.
FIGURE 5.1a A poor risk comparison. SOURCE: Schultz et al., 1986, as
cited in Costello et al., 1988. Reprinted with permission of the Chemical
Manufacturers Association.
It is sometimes assumed that once they are told about risks peo-
ple will systematically minimize their exposures and disregard truly
small risks when they understand how little they are. This encour-
ages comparing the risk in question to other risks that are familiar
to most people with the intent of claiming that the level of the risk
under examination is acceptable. The logic of using risk compari-
son to determine acceptable risk usually runs as follows: since you
OCR for page 99
COMMON MISCONCEPTIONS ABOUT RISK COMMUNICATION 99
RADON RISK CHART
Lifetime
exposure
(picocuries
per liter)
Lifetime
risk of dying
from radon*
(out of 1,000)
Comparable risks of
fatal lung cancer
(lifetime or entire
working life)
75
40
20
10
4
2
1
0.2
2 1 4-Ss4
1 20-380
60-210
7-30
1 -3
~ ~ - ~: :~: I, ~ ~ ~ ~ ~ ~ ~ .
~ ~ ~ ~ ~ :~ ~ ~ ~ ~:~: 1
.~ .~: ~ :~ ~ ~ 1
: ~ -: :~ :~ ~ ~ :~.~: :~ ~:
~,~.~ ~ ~ :~ :~ ~ ~ ~ ~ ~ 1
.~ ~ ~ ~ ~ ~ ~U ~ ~ ~ ~ ~ t ~ ~ ~ ~ W ~ 1
PRINCIPAL WEAKNESSES:
(1) Exposure not
defined (e.g., amount
of time spent indoors).
(2) It is not known
whether most people
accurately perceived
the anchors (i.e.,
asbestos, smoking,
X-rays).
(3) The original uses
colors that may be
misleading.
(4) Does not use a
linear scale.
(5) Uses anchor risks
(i.e., asbestos,
smoking, X-rays) with
different qualitative
attributes.
FIGURE 5.1b A better risk comparison. SOURCE: Smith et al., 1987, as
cited in Costello et al., 1988. Reprinted with permission of the Chemical
Manufacturers Association.
accept the risk of driving an automobile, which is about 240 annual
fatalities per million persons (total population), you also ought to
accept the risk of exposure to X (whatever hazard the communicator
supports), which is, say, 10 annual fatalities per million. This logic
is faulty (Fischhoff et al., 1981a). A homeowner, for example, should
not neglect the potential fire hazard of electrical appliances or gas
stoves and furnaces just because the risk of annual fatality due to
OCR for page 100
100
IMPROVING RISK COMMUNICATION
fire is about one tenth as large as that due to driving an automobile.
Rather, reasonable precautions should be considered with regard to
risks deriving from all the hazards over which one has control. The
level of risk is only one among several factors that deterrn~ne accept-
ability (Fischhoffet al., 1981a; Gould et al., 1988; Slavic, 1987; SIovic
et al., 1980), and the information requirements for an informed de-
cision by private individuals or public officials will generally include
more than the level of risk alone.
BELIEFS ABOUT THE FUNCTIONING OF THE PROCESS
Many problems for risk communication derive from mistaken
beliefs about the nature of the risk assessment, risk management,
and risk communication processes.) It is mistaken to expect scien-
tific information to resolve all important risk issues. In addition,
even when valid scientific data are available, experts are unlikely to
agree completely about the meaning of the data for risk management
decisions. Finally, it is unrealistic to expect easy identification and
understanding of the values, preferences, and information needs of
the intended recipients of risk messages.
Adequacy of the Scientific Formation Base
As is clear from the discussion in Chapter 2, it is unrealistic
to expect complete information about all the various aspects of a
hazard and the risk of exposure to it. But even if the scientific risk
information were perfect, it might not resolve all the issues involved.
The best technical analysis cannot reveal what ought to be done.
Analysis can only estimate the consequences and, in some situations,
the way those expected outcomes compare to other related outcomes.
The adequacy of the information base is an important considera-
tion not only because some statutes as well as current interpretation
of the Administrative Procedures Act require regulatory decisions
to be based on reasoned consideration of the evidence, but also
because risk management decisions should be based on the best
available information rather than arbitrary or unfounded beliefs and
assumptions. It could thus be argued that the information base for
a risk management decision would be inadequate if additional scien-
tific data could provide at reasonable cost a more detailed or more
complete understanding of the phenomena giving rise to the risk in
question. Of course, more scientific data always would be of positive
OCR for page 101
COMMON MISCONCEPTIONS ABOUT RISK COMMUNICATION 101
value under such a criterion, and the difficulty lies in determining
how many resources should be allocated to this particular problem
and how long the decision should be delayed in order to obtain more
data.
Agreement as to the Meaning of Existing Information
There is seldom definitive scientific data about important risk
issues. Science continually develops new, more sophisticated testing
methodologies. Even with the most recent additions it is doubtful
that any substance or product has been, or can be, so thoroughly
tested as to preclude further scientific question. The numbers usually
can only give an estimation of the consequences and, in some situ-
ations, the way those expected outcomes compare to other related
outcomes. Very often regulatory and other risk control decisions
must be taken before all the scientific questions are fully resolved.
In these cases the decision maker will be faced with choosing from
among conflicting, sometimes contradictory interpretations of the
data.
These issues are important because they can strongly affect the
determination of risk concerning a particular substance or activity.
Whether a linear or multistage mode! is used for extrapolation, or
whether a restricted or generalized model is used to compute doses,
estimation of the no observed effect level (NOEL), or the safety
factors used to allow for various kinds of uncertainty, can have sig-
nificant impact on the characterization of risk. Such issues can be
at the center of a controversy and can dominate debate about them
and the related risk messages.
Interpretation of Public Attitudes and Information Needs
Because of the public's ability to make itself heard on risk is-
sues, public opinion does influence the introduction and application
of modern technology. But it is usually a relatively small part of the
general public that makes its views known about a particular issue. It
is therefore useful to distinguish between the passive public (largely
unaware of the issue), the attentive public (aware of the issue and
its ramifications), and the active public (seeking to make its views
known or to affect decisions in other more direct ways). Depending
on the nature of the issue, the source of a risk message may need
to understand the attitudes and information needs of each of these
OCR for page 102
102
IMPROVING RISK COMMUNICATION
different types of potential recipients of risk messages. Both the dif-
ferences among these types of potential recipients and the respective
ease or difficulty of establishing contact with them and determining
their views and information needs contribute to the complexity of
the task.
A few years ago several of the large groups of government and
industry risk managers began seeking out the advice of social scien-
tists because of opposition to their programs in the public (Fischhoff,
1985a). Risk managers typically made confident statements about
public opinion on the basis of anecdotal observation, in contrast to
practicing social scientists, who usually venture carefully qualified
statements only after extensive investigation. Risk managers also
made confident statements about the information the public wants
and uses in particular situations. For the most part both types of
statements were based on a view of "the public" that did not dif-
ferentiate among the general public, the attentive public, and the
active public or among people with different personal values, levels
of exposure, or sensitivities to the hazards in question.
Not only does the level of interest in specific topics vary among
different people, but so also does the way they think about the is-
sues involved. During the last decade researchers have examined
the opinions people express when asked, in a variety of ways, to
evaluate hazardous activities, substances, and technologies (SIovic,
1987~. Psychological research suggests that people's perceptions and
attitudes are not determined solely by the sort of unidimensional
statistics used to describe the magnitude of risks. To many peo-
ple, statements such as, "the annual risk from living near a nuclear
power plant is equivalent to the risk of riding an extra 3 miles in an
automobile," give inadequate consideration to important differences
in the nature of the risks from these two technologies. As noted in
Chapter 3, risk is only one facet of these conflicts (see also Douglas
and Wildavsky, 1982; Short, 1984~. Risk concerns may provide a
rationale for actions taken on other grounds or they may be a surro-
gate for other social or ideological concerns. When this is the case,
communication about risk is off the mark.
STEREOTYPES ABOUT INTERMEDIARIES
AND RECIPIENTS
Some risk communication problems d erive from misconceptions
about the way intermediaries and recipients react to risk messages. It
OCR for page 103
COMMON MISCONCEPTIONS ABOUT RISK COMMUNICATION 103
is mistaken to view journalists and the media always as significant,
independent causes of problems in risk communication. It is mistaken,
as well, to expect people only to want simple, cut-and-dried answers
in every case.
Journalists and the News Media
Many people who are disgruntled with the slowness and appar-
ent incoherence of decision making about risk control or with the
outcomes attribute many of these problems to the news media and
journalists. Some claim, for example, that public concern is "driven
by media coverage rather than by rational scientific analysis" or
that "the media has driven the public insane" (Cohen, 1987~. These
critics claim, for example, that the news media are basically in the
entertainment business and that the only thing that matters is the
ability of a story to attract attention because this sells newspapers
and attracts viewers.
It is true that newspapers, radio and television stations, and the
networks are businesses. And it is true that they must Day attention
to income and profits.
21 ~e , ~ · ~11 ~
But the direct effect on subscriptions or
ac~verr~s~ng Income Is not lively to be In the minds of reporters as
they prepare stories nor in the minds of editors or producers as they
make story assignments, edit copy, or determine the placement of
various stories in that day's newspaper or newscast.
In selecting sync] preparing stories, the reporter is much more
likely to be motivated by events, by what other reporters are paying
attention to, by information provided on a regular basis by sources
he or she has cultivated, by deadlines, and by what interests him
or her as a citizen. The editor or producer will be concerned about
the appeal and impact of the issue or program as a whole. Both, for
their different reasons, will be concerned about the importance of the
stories, their impact, and their drama. The attractiveness of stories
with such appeal will be strong whenever censorship is absent and
there is free and open access to information sources. It is mistaken
to attribute the way the media defines "newswc~rthin~" in nr~t.ir
to crass ecc~nomi~. m~t.i~r-~ elan"
--- rig
Because of their involvement in selecting and preparing stories,
journalists may have a better perception of the audience and its in-
terests than do editors or producers. But that perception is probably
also based on the "convenience sample" with which that journalist
happens to have contact. Journalists and the media play important
OCR for page 104
104
IMPROVING RISK COMMUNICATION
roles in revealing conflicts and sometimes in their resolution. The
media may nurture the development of controversy by serving as a
channel for debate among the major actors in a conflict, and they
can play crucial roles in providing information to citizens during
conflicts (Tichenor et al., 1980~. This latter can be especially impor-
tant since significant portions of the public may never attend to risk
information unless such a conflict attracts their attention.
For the most part, what can be called the national press (the
New York Times, Wall Street Journal, and comparable news organi-
zations) treats risk issues with considerable care and understanding.
But this is not always true, especially at the regional or local level.
The performance of the press in the reporting of risk issues is not
always up to the standards found in other topic areas. Most news
organizations would not tolerate sports or business reporting by re-
porters who do not understand the subject and are unable to correctly
frame those topics. The same is not always true of the reporting of
the technical and social dimensions of risk messages.
Some criticism of the news media emerges from a failure to ex-
amine the structure of the media industry or how journalists work. It
would be more fruitful for risk communicators to try to understand
the pressures and constraints on news gathering than to curse the
sometimes disappointing results. The structure of the industry ?~.n<:3
the incentives and influences that affect the way it works are part
of our social and political system. What is needed are ways to im-
prove risk communication by helping scientists and decision makers
understand how and why journalists do their work and by helping
journalists understand how scientists and decision makers think and
interact.
There are, for example, differences between the structure and
incentives affecting the broadcast media and those affecting the print
media. Material with visual impact will be especially appearing for
television. There also will be differences within segments of the
different media. The focus and approach of science magazines, for
example, differ from those of straight news magazines. National
newspapers differ from regional or local newspapers. Despite these
differences, however, the overall impact of the incentives and influ-
ences on reporters, editors, producers, and so on is more similar in
the various media than different.
Another characteristic of the press worth understanding is that
most reporters dealwith news, not education (Sandman, 1986~. It is
usually the events that make something newsworthy, not the issues
OCR for page 105
COMMON MISCONCEPTIONS ABO UT RISK COMMUNICATION 105
or principles involved. News reporters seldom want to know the ins-
and-outs of risk assessment, how sure the experts are, or how they
found out. They want to know about the number of people affected;
the gravity of the consequences; and the cost of damage, repairs, or
remedies. They pay attention to the vividness with which these can
be presented.
Feature stories, such as those found in Sunday editions or special
broadcasts, can go into much greater depth and offer more complex
treatments. Specialist reporters also pay attention to newsworthi-
ness, imagery, and so forth, but they tend to go into greater depth in
laying out the background and some of the underlying factors that
bear upon the events.
Most journalists care about accuracy and objectivity. Often the
only operational definition of objectivity for journalists is balance
(Sandman, 1986~. They are seldom experts in the topics they cover.
They cannot, as a result, determine for themselves what is true. They
can only try to present the conflicting claims fairly. And because their
job generally is reporting events rather than issues, they get most of
their information from people who are directly involved in the event
and only occasionally seek out uninvolved experts for advice. Some
journalists, especially at the regional and local levels, also emphasize
the reactions of ordinary people. They present the events of concern,
the consequences and their importance, any conflict about outcomes
or responsibilities, and the response of "the man on the street." This
helps people interpret the news in terms of themselves, their families
and their neighbors.
Journalists may seek out those with conflicting claims about the
events in the news. In striving for a balanced coverage, they often
attempt to identify extreme positions about the events or issues.
Not being able to assess which positions have been given greater
credence among the community of experts, they attempt to discover
the range of views. Although they may not present the most extreme
positions-the ones and sevens on a range from one to seven they
will typically Took for individuals expressing we0-defined positions
that bracket the middle of the range of relevant views the twos and
threes and the fives and sixes. Positions that clearly differ in this
way are attractive to the journalist because they define the range
and because their juxtaposition sharpens the drama and heightens
interest.
To be sure, there have been instances in which media coverage
has favored one extreme, such as the television network that showed
OCR for page 106
106
IMPROVING RISK COMMUNICATION
a skull and crossed bones in the background whenever a reporter
spoke about ethylene dibromide (EDB) (Sharlin, 1987~. But there
is also some evidence that even in events with massive attention
and media coverage, the news media seek balance. An extensive
content analysis of media coverage of the nuclear industry accident at
Three Mile Island found the balance between supportive and negative
statements to be, if anything, more reassuring than alarming (Report
of the Public's Right to Information Task Force, 1979; Stephens and
Edison, 1982~.
The Attraction of Decisive Answers
The public often appears to want decisive, clear-cut determi-
nations of risk and descriptions of the appropriate control mea-
sures, especially when the choices they face appear to be simple
dichotomies a product can be used or not used, an incinerator built
or not built. This response is based on fundamental psychological
mechanisms. Most people prefer simplicity to complexity in matters
outside their own field of expertise. In addition, most people are
too busy to spend much time on any particular topic, and some find
it hard to understand why information about risk cannot be put in
concise, decisive terms. Unfortunately, one seldom knows how often
or in what mixes these various situations obtain.
Sometimes, however, people prefer to have the options laid out
for them and to be given the choice of selecting the one they prefer.
This is most common when the risk control measures require action
by the individual. Examples include using seat belts, choosing among
medical treatments, and changing sexual practices to curb the spread
of contagious diseases such as hepatitis or AIDS.
Several things may influence people's preference for decisive or
ambiguous information: the degree to which they as individuals ex-
ercise control over exposure or remediation, the importance they
attach to the issue, and their tendency to be risk averse or risk seek-
ing. That different segments of the population may prefer decisive or
equivocal information about a particular risk can make the job of the
risk communicator more difficult. It may even be that individuals
prefer different types of information at different times during the
course of discovery, analysis, and control of a hazard.
This chapter has discussed some of the more important mis-
conceptions about risk communication. The next chapter addresses
OCR for page 107
COMMON MISCONCEPTIONS ABOUT RISK COMMUNICATION 107
directly what we believe to be the most important problems con-
fronting the practice of risk communication.
NOTE
1. These and other relevant terms are defined in a list given in Appendix E.
Representative terms from entire chapter:
risk messages
