weighing risks and benefits
TRANSCRIPT
Weighing Risks and Benefits Sven Ove Hansson
ABSTRACT: It is almost universally acknowledged that riskshave to be weighed against benefits, but there are different
ways to perform the weighing. In conventional risk analysis,collectivist risk-weighing is the standard. This means that anoption is accepted if the sum of all individual benefits out-
weighs the sum of all individual risks. In practices originatingin clinical medicine, such as ethical appraisals of clinical trials,individualist risk-weighing is the standard. This implies a muchstricter criterion for risk acceptance, namely that the risk to
which each individual is exposed should be outweighed bybenefits for that same individual. The different choices of risk-weighing methods in different policy areas seem to have
emerged from traditional thought patterns and social relations,rather than from explicit deliberations on possible justifica-tions for the alternative ways to weigh risks against benefits. It
is not obvious how the prevalent differences in risk-weighingpractices can be reconstructed in terms of consistent underly-ing principles of preventive health or social priority-setting.
1. The basic risk-weighing principle
The world that we live in is not free of risks, and
neither can we make it so. Some risks have to be
accepted in order to obtain benefits that would
otherwise be inaccessible. It seems undeniable that
risks have to be weighed against benefits. A risk
should only be taken if it brings with it some benefit
that makes it worth taking. We can express this
intuition as follows:
The basic risk-weighing principle:A risk is acceptable if and only if it is outweighed by agreater benefit.
This principle corresponds to common, and generally
accepted, patterns of argumentation about risks, both
in private and public life. Going back into a burning
building may be worth the risk if the purpose is to
save a sleeping child, but it should not be done in
order to recover a left-behind wallet. The risk is the
same in the two cases, but the expected gain is
incomparably higher in the first case.
However, although the basic risk-weighing princi-
ple captures important aspects of our intuitions about
risk acceptance, it is insufficiently specified. There are
different ways to weigh risks against benefits, and
different variants of risk-weighing have been chosen
in different policy areas. It is the purpose of the
present contribution to clarify the nature of these
variants. Before they are introduced, a few more
general comments are in order about the basic risk-
weighing principle.
First, as it stands the principle is insufficiently
decision-guiding. The major reason for this is that it
only requires a positive net benefit, and does not
differentiate between alternative risk-taking actions
that differ widely in the size of the net benefit. (Net
benefit¼ benefits minus risks.) For an example, sup-
pose that we have a choice between two life-saving
drugs for patients with a certain condition. The two
drugs are equally efficient, and the only known dif-
ference between them is that one of them gives rise to
cirrhosis in 1 out of 100 patients, whereas the other
has that side effect in 1 out of 5000 patients.
According to the above formulation of the basic risk-
weighing principle, both drugs are acceptable. This is
contrary to common moral intuitions and to well-
established ethical practices in clinical medicine.
Obviously, only the drug with the lowest risk of cir-
rhosis should be used.
It is a relatively easy matter to adjust the basic risk-
weighing principle so that it guides choices between
different alternatives, rather than determining the
acceptability of isolated alternatives. The most obvi-
ous way to do this is to require that one chooses one
of the alternatives that have the highest net benefit.
Other choice-guiding criteria are also possible. It is
for instance possible to construct the set of allowable
alternatives so that it includes not only the alterna-
tives with maximal net benefit but also those
with near-maximal net benefit (with some suitable
Topoi 23: 145–152, 2004.� 2004 Kluwer Academic Publishers. Printed in the Netherlands.
definition of near-maximality).1 For our present
purposes, the choice of an optimization/satisficing
method can be left open. Therefore, the basic risk-
weighing principle will not be reformulated along any
of these lines. Instead, the following reformulation
will be used, that is intended to keep this choice open:
The basic risk-weighing principle, revised:A risk is acceptable to the extent that it is outweighed by a
greater benefit.
Secondly, the terms ‘‘risk’’ and ‘‘benefit’’ exhibit a
strange asymmetry. Whereas ‘‘risk’’ denotes disad-
vantages that may or may not materialize, ‘‘benefit’’
denotes advantages of which one is sure. It would be
more symmetric to weigh risks against chances or
benefits against harms.
There are cases in which one chooses between
combinations of risks and benefits, but also cases with
a choice between combinations of risks and chances.
Investment decisions involve the weighing of risks
against chances, i.e. both advantages and disadvan-
tages are uncertain. The same applies to clinical
treatment decisions in which the available therapies
have significant risks.
The general problem that should be addressed is
not the weighing of uncertain negative effects (risks)
against certain positive effects (benefits). Instead, it is
the weighing of certain and uncertain negative effects
(harms and risks) against certain and uncertain po-
sitive effects (benefits and chances). Hence, good
arguments can be made in favour of terminological
reform. However, the traditional risk-benefit termi-
nology is entrenched and not easily changed. It will be
used here, with the understanding that it refers to the
general case just described.
Thirdly, the basic risk-weighing principle has a
strong consequentialist bias. Weighing is not easily
accommodated in deontological or rights-based eth-
ics, and terms such as ‘‘risk’’, ‘‘benefit’’ (and for that
matter ‘‘harm’’ and ‘‘chance’’) give a strong indica-
tion that actions are evaluated according to their
consequences. Generally speaking, consequentialism
should not be taken for granted in discussions of risk
(Hansson, 2003). However, in an investigation of risk-
weighing it is methodologically convenient to accept
the consequentialism inherent in the basic risk-
weighing principle as a starting-point. Its weaknesses
should be uncovered in the analysis.
2. Collectivist or individualist risk-weighing
The weighing of risks against benefits is a central
feature in a large number of social practices. A closer
study will reveal that it is performed in fundamen-
tally different ways in different application areas. The
crucial difference concerns whether or not benefits
for one person are allowed to outweigh harms to
another person. We can call this the issue of inter-
personal compensability. It has unfortunately often
been conflated with the related but distinct issue of
interpersonal comparability. Even if it can be estab-
lished that a benefit is greater than a harm, the
benefit need not cancel out the harm in the same
unproblematic way as a loss is (presumably) can-
celled out by a gain in the calculations of an inves-
tor.2 The fact that a certain loss for Ms. Black is
smaller than a certain gain for Mr. White does not
suffice to make it allowable for Mr. White, or anyone
else, to perform an action that leads to this particular
combination of a loss for Ms. Black and a gain for
Mr. White. For that conclusion to follow, another
premise must be added, namely the premise of
interpersonal compensability.3 Interpersonal compa-
rability does not imply interpersonal compensability,
but they are nevertheless closely related since the
former is a necessary prerequisite for making the
latter operative.
If full interpersonal compensability is assumed,
then the basic risk-weighing principle can be specified
as follows:4
The collectivist risk-weighing principle:An option is acceptable to the extent that the sum of all
individual risks that it gives rise to is outweighed by the sumof all individual benefits that it gives rise to.
If on the other hand interpersonal incompensability is
assumed, then we can instead specify the risk-weigh-
ing principle in the following way:
The individualist risk-weighing principle:An option is acceptable to the extent that the risk to whicheach individual is exposed is outweighed by benefits for that
same individual.
Clearly, intermediate standpoints are possible,
that allow for partial rather than complete compen-
sability.
146 SVEN OVE HANSSONSVEN OVE HANSSON
The practical consequences of how the basic risk-
weighing principle is specified can be illustrated with
two examples. For the first of these, suppose that
your physician considers including you in a group of
patients who will receive a new, experimental treat-
ment. Such a treatment clearly involves risks and
benefits that have to be weighed against each other.
This can be done according to either the collectivist or
the individualist risk-weighing principle. First, sup-
pose that the physician employs the collectivist risk-
weighing principle. Then she will consider it justified
to include you in the study if the risk is outweighed by
the total social benefit, which includes the expected
gains from the study for future patients. This may of
course be the case even if the risks to which you are
exposed are not outweighed by the expected gains to
you personally. Next, suppose that she instead makes
use of the individualist risk-weighing principle. Then
she will not propose that you participate unless she
believes that the risks to which you will be exposed
are outweighed by advantages for you personally
(primarily in the form of chances of improved health
due to the experimental treatment).
In the second example it has been proposed to site
a chemical factory in your neighbourhood. Some of
your neighbours protest against these plans, claiming
that pollutants from the factory will cause unaccept-
able risks for themselves and their children. Again, it
makes a large difference if the collectivist or the
individualist risk-weighing principle is used to ap-
praise the situation. According to the collectivist
principle, it is justified to build the factory if the total
social benefits that it brings about outweigh the
totality of the risks that it gives rise to. Arguably, the
factory contributes to economic growth and therefore
to the welfare of every inhabitant in the country.
Although these gains are very small, they are attained
by a very large number of persons, and they may
therefore outweigh the risks that the neighbours are
exposed to. In contrast, the individualist risk-weigh-
ing principle requires that each and every concerned
individual obtains benefits from the factory that are
outweighed by the risks to which she is exposed.5
As these examples show, the choice between col-
lectivist and individualist risk-weighing can have a
large impact on policy outcomes. In the following two
sections, we are going to have a closer look at policy
areas that are dominated by each of these risk-
weighing methodologies.
3. Risk analysis
The dominant systematic approach to risk is the
discipline of risk analysis. Modern risk analysis grew
out of the various reactions that public opposition to
new technologies gave rise to in the 1960s (Otway,
1987; Hansson, 1993). Some of the earliest studies in
the field aimed at determining a level of ‘‘acceptable
risk’’ that should be accepted irrespective of the
associated benefits. However, with the exception of a
marginal discourse on ‘‘de minimis risk’’,6 this ap-
proach is now defunct. Today, the weighing of risks
against benefits is conceived as a central task in risk
analysis.
Risks and benefits are different types of entities,
and not immediately comparable. The practices that
are used in risk-benefit analysis to achieve compara-
bility can be summarized as two technical procedures.
First, uncertain outcomes are weighed according to
their probabilities, so that for instance a risk of one in
50 that a person will die is counted as the death of
0.02 persons. In other words, risks are assessed
according to their statistical expectation values.7 (It is
also common to use the word ‘‘risk’’ to denote the
expectation value, i.e. the product of the probability
of an event and a measure of the magnitude of the
harm that it gives rise to.) A proponent of that
methodology recently motivated it as follows:
The only meaningful way to evaluate the riskiness of atechnology is through probabilistic risk analysis (PRA). APRA gives an estimate of the number of expected health
impacts-e.g., the number of induced deaths-of the tech-nology, which then allows comparisons to be made with thehealth impacts of competing technologies so a rational
judgment can be made of their relative acceptability. Noonly is that procedure attractive from the standpoint ofscientific logic, but it is easily understood by the public.
(Cohen, 2003, p. 909)
Secondly, monetary values are assigned to all out-
comes, including deaths, so that an overall value can
be calculated for each alternative under consider-
ation. Various methods to convert lives to monetary
values have been deviced, making use of expected
earnings, actual sums paid to save lives, willingness to
pay for reduced risks of death, etc.8 Through the
combination of these two procedures – probabilistic
weighing and conversion to money – full compara-
bility of risks and benefits is obtained, in a technical
WEIGHING RISKS AND BENEFITSWEIGHING RISKS AND BENEFITS 147
sense. It is implicitly (and seemingly unreflectingly)
taken for granted that comparability implies com-
pensability.
Much of the early work in risk analysis was fo-
cused on chemicals and on nuclear technology, the
same risk factors that public opposition targeted on.
Today, risk analysis employing collectivist risk-
weighing is applied to a wide category of social areas,
such as the health impacts of air pollution (Pandey
and Nathwani, 2003) and radioactive waste reposi-
tories (Cohen, 2003), the effectiveness of airbag
regulation (Thompson et al., 2002) and accident-
preventive measures in road construction (Usher,
1985), and the effectiveness of efforts to detect
asteroids or comets that could strike the earth
(Gerrard, 2000), just to mention a few examples.
Risk analysis is a large and ramified discipline that
includes a multitude of methodologies. However, the
discipline is strongly dominated by standard risk-
benefit analysis with its adherence to full compensa-
bility and to collectivist risk-weighing. This domi-
nance can be seen for instance in risk-analytical
approaches to issues such as uncertainty and justice.
Treatments of uncertainty in risk analysis usually take
the form of determining a distribution of ‘‘risk val-
ues’’ (see for instance von Stackelberg et al., 2002).
Discussions of justice tend to focus on the distribu-
tion of the aggregate expectation value (‘‘risk’’)
among population strata. This means that collectivist
risk-weighing is the starting-point, to which consid-
erations of justice are added.
The dominance of collectivist risk-weighing can
also be seen from prevalent attitudes to the so-called
NIMBY (not in my backyard) phenomenon. By
NIMBY is meant that a person or group or persons
protest against the siting in their neighbourhood of a
facility that will be disadvantageous to themselves but
advantageous to society as a whole. Risk analysts
who condemn NIMBY reactions seem to take it for
granted that collective risk-weighing is justified in the
cases in question.9
4. Medical risk assessment
One of the most well-developed practices that makes
consistent use of individualist risk-weighing is re-
search ethics as applied to clinical trials. In a clinical
trial, each patient is randomly assigned to one of
several groups that receive different treatments. The
standard approach to medical research ethics, as
codified in the Helsinki declaration and the practices
with which it is connected, sets up two conditions for
the inclusion of a patient in a clinical trial. The first of
these is the patient’s informed consent.10 The second
is a state of genuine uncertainty on whether or not
participation in the trial is better for the patient than
the standard treatment that she would otherwise re-
ceive. The latter requirement is of particular interest
in the present context. A common way to express it is
that there should be equipoise or uncertainty between
the different treatments.11 By this is meant a state of
knowledge in which there are no compelling reasons
to choose one treatment over the other. There should
be ‘‘credible doubts’’ about the ‘‘relative net thera-
peutic advantage’’ of the two interventions, and no
third intervention should be available that is prefer-
able to at least one of them (London, 2001). These
doubts constitute the justification for assigning the
patient randomly to one of the treatments.
Different views have been expressed on whose
assessment of the evidence should determine whether
or not equipoise holds: the individual physician, the
individual patient, the medical community, or some
larger community that includes patients and perhaps
others (London, 2001; Sackett, 2001). Some authors
claim that equipoise refers to the state of mind of the
individual physician who is uncertain about which
treatment is best for the patient. However, it would
then be difficult if not impossible to conclude that a
physician ever errs in enrolling a patient in a trial. So
long as the physician claims that he or she was uncer-
tain, he or she cannot be said to be wrong even if this
uncertainty was due to ignorance (Weijer et al., 2000).
Amore promising proposal is that equipoise should be
determined in relation to competent medical practice,
i.e., practice that is within the bounds of the standard
of care. Clinical trials can then be performed if there is
disagreement in the community of competent medical
professionals about which treatment is best.12 A fur-
ther proposal is to allow for equipoise in a wider group
of decision-makers, that includes both physicians and
patients (Karlawish andLantos, 1997). Amajor reason
for extending decision-making on clinical trials to non-
experts is that the choice between treatments is in part a
value issue that should not be delegated to experts.
(The choice between lumpectomy and radical mastec-
tomy is one of many examples of this.)
148 SVEN OVE HANSSONSVEN OVE HANSSON
However, irrespective of how equipoise is deter-
mined, it refers to the balance between risks and
benefits (or risks and chances) for the individual pa-
tient. Hence, the standard ethical approach to clinical
trials adheres strictly to the individualist risk-weigh-
ing principle. This is particularly interesting in view of
the fact that clinical trials are performed for the sake
of future patients, rather than the patients partici-
pating in the trials. It is difficult to see how a physi-
cian searching for the best treatment for an individual
patient could end up recommending that the choice of
a treatment should be made by a randomizing device.
The use of individualist risk-weighing as an inclusion
criterion can be seen as a corrective, intended to en-
sure that the interests of individual patients are not
sacrificed in studies that are primarily undertaken for
the benefit of a wider collective.
According to the received ethical approach to
clinical trials, both equipoise and informed consent
are required. The latter cannot replace the former. In
other words, current principles of medical ethics do
not allow a person to sacrifice her own interests by
taking part in a clinical trial that is beneficial to a
wider community but known to be to some extent
harmful to herself. This is in stark contrast to the
collectivist risk-weighing that dominates the practice
of risk analysis as described in Section 3. To mention
just one example, critics of NIMBY reactions require
that potential neighbours of a contested facility sac-
rifice their own interests by consenting to a siting that
is beneficial to a wider community but potentially
harmful to themselves.
Proposals have been made to reform the received
ethical criteria for clinical trials. Fears have been
expressed that the current approach may prevent
some of the clinical trials that are necessary for
medical progress. This, it is argued, can be avoided by
giving some weight to ‘‘utilitarian’’ considerations,
i.e., to the expected benefits for non-participating
patients who will receive improved treatment due to
the new knowledge obtained in the trial (Gifford,
1995; Longwood, 1983). However, there is strong
resistance to such proposals in the medical ethics
community, partly for historical reasons. Modern
medical research ethics largely originated as a ‘‘pro-
test movement’’ against dangerous experiments per-
formed by physicians on their patients, justifying
them with reference to expected benefits for future
patients.
Some authors have claimed that altruistic motives
for participation in a clinical trial should be accepted
(Amdur and Biddle, 2001; Veach, 2002). Appeal to
altruism has precedents in other medical practices.
Patients are routinely advised to complete an antibi-
otics regimen in order not to contribute to the
development of resistant microorganisms, even if it
would be marginally better for their own wellbeing to
end the cure. Patients with contagious diseases are
advised to take various measures to protect others
from contracting the disease. The effect of accepting
altruism in clinical trials would be that (some) vol-
untary risk-taking for the benefit of future patients
would be accepted.
In addition to clinical trials there are other areas of
risk discourse in which the individualist mode of risk-
weighing is strictly adhered to. Dietary advice is one
of these areas. As one example of this, although fish is
generally speaking healthy food, contaminants in fish
caught in certain waters give reason to recommend
limits in fish consumption. Such recommendations
are based on the positive and negative health effects
on the individual (and in the case of pregnant or
breast-feeding women, on corresponding effects on
the child) (Knuth et al., 2003). It would be regarded
as inappropriate to include other factors in these
deliberations, such as the effects of diminished fish
consumption on employment in the fishing industry
or on regional economics.
5. A hybrid risk-weighing principle
The collectivist and individualist risk-weighing prin-
ciples are not the only ways in which the basic risk-
weighing principle can be specified. A third variant
should be mentioned, that corresponds to patterns of
thought that dominate in certain social areas.
The hybrid risk-weighing principle:
An option is acceptable to the extent that the risk to whicheach individual is exposed is outweighed by the totality ofbenefits.
The hybrid principle measures benefits on the collec-
tive level and risks on the individual level. Suppose
for instance that we apply the hybrid principle to risks
in space exploration. Then the accepted individual
risk level in a space operation will be determined on
WEIGHING RISKS AND BENEFITSWEIGHING RISKS AND BENEFITS 149
the basis of the overall benefits of the operation. Just
as the collectivist principle, the hybrid principle fo-
cuses on total benefits rather than on benefits for the
individual person. However, just like the individualist
principle, it focuses on risk levels for individuals ra-
ther than on total (aggregated) risk. Contrary to the
collectivist principle, neither the hybrid nor the indi-
vidualist principle allows for higher individual risk
levels if the number of exposed persons is propor-
tionately reduced.
The hybrid principle has some intuitive appeal, but
it has the conceptual disadvantage of stretching the
meaning of ‘‘weigh’’. It may therefore be more accu-
rate to express it as follows:
The hybrid risk-weighing principle, revised:
An option is acceptable to the extent that the risk to whicheach individual is exposed is reasonable against the back-ground of the totality of benefits.
A major application area for the hybrid risk-
weighing principle is the setting of occupational
exposure limits. These are maximal allowed exposures
for individual workers (irrespective of the number of
exposed persons). In practice, most if not all of these
values are based on a compromise with technical and
economic feasibility, that is assessed on an aggregated
social level. However, there is an unfortunate tradi-
tion in this area of incorrectly announcing the out-
come of such compromises as values based exclusively
on medical or scientific information (Hansson,
1998).13
In radiation protection two regulatory methods are
combined in order to limit exposures. One of these is
an individual exposure limit of the same type as in
occupational hygiene. The other consists in limiting
the total exposure to radiation according to the
ALARA principle (as low as reasonably achievable).
The individual exposure limit is essentially based on
hybrid risk-weighing, whereas the ALARA principle
is based on collectivist risk-weighing. Judging by
ongoing debates in leading radiation protection cir-
cles, the system will probably be changed in the
direction of a greater emphasis on individual expo-
sure limits and a corresponding de-emphasis on col-
lective exposure.14
One more area should be mentioned in which hy-
brid risk-weighing takes place, namely the use of
healthy volunteers in medical experiments. In phar-
macological research, drugs are often administered to
healthy volunteers from whom blood samples and
other measurements are obtained in order to deter-
mine the metabolism and pharmacokinetics of the
drug. Participation in such experiments cannot be
based on equipoise, since participants typically have
no personal medical gain from them. Instead, par-
ticipation is based on (altruistic) informed consent to
accept (small) individual risks in order to contribute
to expected advantages to humanity.
6. Conclusion
We have found that the basic risk-weighing principle,
the idea that risks should be weighed against benefits,
can be applied in widely different ways, as expressed
in the collectivist, individualist, and hybrid variants of
the principle. The choice between these variants has
large effects on policy outcomes.
We have also seen that different variants of the
principle dominate in different policy areas. These
differences seem to have emerged from traditional
thought patterns and social relations in the respective
areas, rather than from explicit deliberations on pos-
sible justifications for the different ways to weigh risks
against benefits. Hence, the individualist risk-weighing
principle has a strong standing in social practices that
have their origins in the physician-patient relation-
ship. This is not surprising, given the strong emphasis
in medical ethics on the physician’s role as a trustee for
the patient’s medical welfare. (Beauchamp and Chil-
dress, 2001, p. 312). However, the effect is that indi-
vidual risk-weighing dominates in those areas of
preventive health that have grown out of medical
practices, whereas collective risk-weighing dominates
in many other areas. The health effects of chemical
substances in the atmosphere are in general evaluated
in terms of collectivist risk-weighing, whereas those of
substances in food are evaluated in terms of individ-
ualist risk-weighing.15 It is not obvious how differ-
ences such as this can be reconstructed with reference
to consistent underlying principles of preventive
health or social priority-setting.
The different ways to weigh risks all have their
advantages and disadvantages. With individualist
risk-weighing we avoid sacrificing individuals for the
sake of collective goals. It is precisely in order to
avoid such sacrifices that this type of weighing is used
150 SVEN OVE HANSSONSVEN OVE HANSSON
in medical research ethics. On the other hand, there
are social settings in which the individualist risk-
weighing principle will lead to stalemates and allow
minorities to prevent social progress (Hansson, 2003).
Hybrid risk-weighing can be seen as an attempt to
combine some of the advantages of collective risk-
weighing with some of those of the individualist ap-
proach. However, there may also be other ways to
obtain such a compromise.
We clearly need open-minded studies and discus-
sions on how risk-weighing is and should be per-
formed. The mechanisms that have led to the choice
of different risk-weighing methods in different social
contexts should be investigated. Possible motivations
for using different methods in different policy areas
should be critically assessed. Not least, it is an
important task to develop new methods of risk-
weighing, in particular in the form of reasonable and
principled compromises between the two extreme
positions that now dominate the field, namely those
represented by the collectivist and the individualist
risk-weighing principles.
Notes
1 Both the optimizing and the satisficing criterion providechoice-guidance even in the unfortunate cases in which all
options have a negative net benefit. This is an improvementover the original formulation of the basic risk-weighingprinciple.2 The unreflecting acceptance of interpersonal compensabil-ity can be seen as an instance of what I have elsewhere calledthe ‘‘tuxedo syndrome’’, i.e. the tendency to abstract from the
complex features of most real-world decision problems thatdistinguish them from dealings at the roulette table (S. O.Hansson, submitted for publication).3 Compensability does not either necessarily hold in all
intrapersonal cases, i.e. cases in which the gains and lossespertain to one and the same person. Even if the sum of the(negative) value of losing a toe and the (positive) value of
obtaining a certain sum of money is exactly zero, a transactionleading to these two changes of one’s condition need not be anunproblematic zero-sum affair.4 An assumption of methodological individualism is madehere, i.e. it is assumed that all positive and negative effects ofan option are decomposable into effects on specific individuals.Hence, the possibility of irreducibly collective or impersonal
harms and benefits is not taken into account.5 These benefits may of course include compensations fromthe company (Hansson and Peterson, 2001).6 For an overview of de minimis arguments, see Peterson(2002).
7 For appraisals of this technique, see Hansson (1993) andHansson (2001).8 For a critical appraisal, see Mishan (1985).9 For a critical discussion of how the NIMBY concept is usedin the risk literature, see Luloff et al. (1998).10 Certain exceptions are allowed for research that can only
be performed on patients unable to give informed consent.11 The term ‘‘equipoise’’ is more common in North America,and the term ‘‘uncertainty principle’’ in Europe (Weijer et al.,2000; Sackett, 2000a). Some authors use the two terms in
parallel with different meanings. Hence, Rolleston (2001) andothers use the term ‘‘clinical equipoise’’ for the criterion thatshould be used by a research ethics board when deciding
whether to allow a clinical trial, whereas they use the term‘‘uncertainty principle’’ for the criterion to be applied by aphysician when deciding whether or not to enter patients into a
trial.12 Gifford, 1995; Weijer and Glass, 2002; Weijer et al., 2000;Shapiro et al., 2000; Sackett, 2000b.13 In this context it may be of some interest to note that therole of physicians was very limited in the pioneering years ofoccupational exposure limits. The first TLV (threshold limitvalues) committee of the American Conference of Govern-
mental Industrial Hygienists was formed in the 1940s bychemists, and contained no single physician. As late as in 1966the Industrial Medical Association publicly complained that
only 4 out of the 12 members of the TLV committee had amedical education (Golz et al., 1966; Ziem and Castleman,1989).14 For an overview and critical appraisal of this discussion,see Wikman (in press).15 As noted above, the effects of occupational exposure is
evaluated according to the hybrid risk-weighing principle.
References
Amdur, R. J., and Biddle, C. J.: 2001. ‘An algorithm forEvaluating the Ethics of Placebo-controlled Trial’, Inter-
national Journal of Cancer 96, 261–269.Beauchamp, T. L., and Childress, J. F.: 2001, Principles of
Biomedical Ethics. 5th ed., Oxford: Oxford University Press.Cohen, B. L.: 2003, ‘Probabilistic Risk Analysis for a High-
Level Radioactive Waste Repository’, Risk Analysis 23,909–915.
Gerrard, M. B.: 2000, ‘Risks of Hazardous Waste Sites Versus
Asteroids and Comet Impacts: Accounting for the Dis-crepancies in US Resource Allocation’, Risk Analysis 20,895–904.
Gifford, F.: 1995, ‘Community-equipoise and the Ethics ofRandomized Clinical Trials’, Bioethics 9, 127–148.
Golz, H. H. et al.: 1966, ‘Report of an Investigation of Threshold
Limit Values and Their Usage’, Journal of Occupational Med-icine 8, 280–283.
Hansson, S. O.: 1993, ‘The False Promises of Risk Analysis’,Ratio 6, 16–26.
WEIGHING RISKS AND BENEFITSWEIGHING RISKS AND BENEFITS 151
Hansson, S. O.: 1998, Setting the Limit. Occupational HealthStandards and the Limits of Science. Oxford: Oxford Uni-versity Press.
Hansson, S. O.: 2001, ‘The Modes of Value’, PhilosophicalStudies 104, 33–46.
Hansson, S. O.: 2003, ‘Ethical Criteria of Risk Acceptance’,
Erkenntnis 59, 291–309.Hansson, S. O., and Peterson, M.: 2001, ‘Rights, Risks, and
Residual Obligations’, Risk Decision and Policy 6, 1–10.Karlawish, J. T. and Lantos, J.: 1997, ‘Community Equipoise
and the Architecture of Clinical Research’, CambridgeQuarterly of Healthcare Ethics 6, 385–396.
Knuth, B. A., Connelly, N. A., Sheeshka, J., and Patterson, J.:
2003, ‘Weighing Health Benefit and Health Risk Informa-tion when Consuming Sport-Caught Fish’, Risk Analysis23, 1185–1197.
London, A. J.: 2001, ‘Equipoise and International Human-Subjects Research’, Bioethics 15, 312–332.
Longwood, M.: 1983, ‘Sins of Omissions: The Non-treatmentof Controls in Clinical Trials, I’, Aristotelian Society, Sup-
plementary volume 57, 207–222.Luloff, A. E., Albrecht, S. L., and Bourke, L.: 1998, ‘NIMBY
and the Hazardous and Toxic Waste Siting Dilemma: The
Need for Concept Clarification’, Society and Natural Re-sources 11, 81–89.
Mishan, E. J.: 1985, ‘Consistency in the Valuation of Life: A
Wild Goose Chase?’, in E. F. Paul, F. D. Miller, Jr., and J.Paul (eds.), Ethics and Economics, Oxford: Basil Blackwell,pp. 152–167.
Otway, H.: 1987, ‘Experts, Risk Communication, andDemocracy’, Risk Analysis 7, 125–129.
Pandey, M. D. and Nathwani, J. S.: 2003, ‘Canada WideStandard for Particulate Matter and Ozone: Cost-benefit
Analysis Using a Life Quality Index’, Risk Analysis 23, 55–67.
Peterson, M.: 2002, ‘What is a De Minimis Risk?’, Risk
Management 4, 47–55.Rolleston, F.: 2001, ‘Uncertainty About Clinical Equipoise’,
CMAJ 164, 1831.
Sackett, D. L.: 2000a, ‘Why Randomized Controlled TrialsFail But Needn’t: 1. Failure to Gain ‘Coal-face’ Commit-
ment and to Use the Uncertainty Principle’, CMAJ 162,1311–1314.
Sackett, D. L.: 2000b, ‘Equipoise, A Term Whose Time (if it
Ever Came) Has Surely Gone’, CMAJ 163, 835–836.Sackett, D. L.: 2001, ‘Uncertainty About Clinical Equipoise.
The Author Responds’, CMAJ 164, 1831–1832.
Shapiro, S. H. et al.: 2000, ‘Why Sackett’s Analysis of Ran-domized Controlled Trials Fails, But Needn’t’, CMAJ 163,834–835.
Thompson, K. M., Segui-Gomez, M., and Graham, J. D.:
2002, ‘Validating Benefit and Cost Estimates: The Case ofAirbag Regulation’, Risk Analysis 22, 803–811.
Usher, D.: 1985, ‘The Value of Life for Decision-making in the
Private Sector’, in E. F. Paul, F. D. Miller, Jr., and J. Paul(eds.), Ethics and Economics, Oxford: Basil Blackwell,pp. 168–191.
Veach, R. M.: 2002, ‘Indifference of Subjects: An Alternativeto Equipoise in Randomized Clinical Trials’, Social Phi-losophy and Policy 19, 295–323.
von Stackelberg, K. E. et al.: 2002, ‘Importance of Uncertainty
and Variability to Predicted Risks from Trophic Transfer ofPCBs in Dredged Sediments’, Risk Analysis 22, 499–512.
Weijer, C. et al.: 2000, ‘Clinical Equipoise and Not the
Uncertainty Principle is the Moral Underpinning of theRandomised Controlled Trial’, BMJ 321, 756–757.
Weijer, C. W. and Glass, K. C.: 2002, ‘The Ethics of Placebo-
controlled Trials’, New England Journal of Medicine 346,382–383.
Wikman, P.: in press, ‘Trivial Risks and the New Radiation
Protection System’, Journal of Radiological Protection.Ziem, G. E. and Castleman, B. I.: 1989, ‘Threshold Limit
Values: Historical Perspectives and Current Practice’,Journal of Occupational Medicine 31, 910–918.
Royal Institute of Technology
Philosophy Unit
Teknikringen 78
100 44 Stockholm
Sweden
E-mail: [email protected]
152 SVEN OVE HANSSONSVEN OVE HANSSON