Risk communication: Why we need
Not involving patients in important medical decisions is also
understandable information
ethically unjustifiable, as it is their health that is at stake.
It is premature to give up on people’s ability to
This is particularly important as patients and physicians do
understand health statistics. The example of the pill scare
not always have the same preferences, and not even the
above not only illustrates that health statistics can be
severely misunderstood, but also that the representationmatters. Had the absolute risk increase (“one more in
The recent increase in cases of progressive multifocal
7,000”) of the third generation pills been presented
leukoencephalopathy (PML) for people with MS who were
instead of the relative risk increase (“100%”), there
treated with natalizumab (Tysabri) exemplified those
Wolfgang Gaissmaier, Harding Center for Risk Literacy, Max Planck Institute for Human Development, Berlin, Germany
probably would not have been a pill scare at all (and
differences. It turned out that patients would accept a
higher risk of this extremely severe side effect than
physicians: While only 51% of physicians would accept an
Relative risks cannot only create fears. They are even
event rate of more than two in 10,000, 83% of patients
“In this world, nothing is certain except death and taxes”
statistics that they “afford one of the few examples in which the
more commonly used to make treatment effects look
would do so (Figure 2)8. (Note that the current estimate of
Benjamin Franklin already noted in 1789, on the eve of the
use (or abuse) of mathematical methods tends to induce a
bigger. An advertisement of Lipitor, for instance, hailed the
the actual event rate is about one in 1,000).
French Revolution. This ironic statement nicely illustrates that
strong emotional reaction in non-mathematical minds”. It
drug as cutting the risk of stroke by nearly half. In
everything in life is laden with risk and that we are constantly
complained that for “most of us figures impinge on an
absolute terms, however, the benefits were rather small,
Many of the more cautious physicians probably had
at the mercy of this uncertainty. Even nowadays, however,
educational blind spot” – even for physicians. And it still holds
as after four years, 2.8% of patients taking placebo had a
the best interest of their patients in mind, but some also may
people are uneasy about uncertainty, and many anxiously
true today that big parts of the population have difficulties in
have had defensive reasons as they could be afraid
strive towards a certainty that does not exist. Yet society
understanding numerical information – there is collective
to be held responsible if severe side effects occurred.
needs people who learn to cope with risks and deal with
statistical illiteracy, as a few examples in Table 1 illustrate3.
Many studies show that people, patients as well as
At least in other medical domains, such as prostate cancer
them in an informed way. The general lack of training to deal
physicians, understand the statistical information much
screening, it is well documented that there are many
with risks in today’s technological society has become a
In recent years, an effort has been made to involve patients
better when they are presented as absolute risks than as
physicians who would recommend screening although they
problem, as the following example illustrates:
more strongly by sharing medical decisions between physicians
relative risks6. Difficulties in understanding statistical
do not believe in its effectiveness, often for legal reasons9.
and patients. Yet statistical illiteracy poses a severe obstacle for
information about health should not only be looked for in
When the British press announced in October 1995 that
shared decision making, which relies on the exchange of
our mind and our genes. Rather, the same information can
the third generation of oral contraceptive pills increase
information between the physician and the patient and the
either be represented in a nontransparent format to create
the risk of potentially life-threatening blood clots in the
involvement of both patient and physician in making the
confusion, fear or undue enthusiasm about a particular
legs or lungs by 100%, many women reacted with fear
decision. This requires that both patients and doctors
drug, or it can be transparently represented to foster
and decided not to take this pill anymore. This ‘pill scare’
understand the benefits and harms of different treatment
insight. Numerous methods have already been developed
led to an estimated 13,000 additional abortions in the
options. A risk communication based on misunderstandings,
to convey quantitative information effectively, including a
following year, increasing the cost for the National Health
however, renders the “informed” in informed shared decision
variety of graphical representations7. Service for abortion provision by about £4 to 6 million (Figure 1)1. But what did the increase by 100% actually mean? The studies on which the warning was based had
Should one thus conclude that patients are not, and probably
shown that the absolute risk had increased from one to
never will be, able to evaluate health benefits and risks
two out of every 7,000 women.
accurately? And that, as a consequence, there is a need for abenevolent paternalism that uses methods of propaganda to
The example illustrates a problem in the communication of
persuade them to do what is considered best for them, or by
% Correct answer
statistical information about health, and this problem was
nudging them to make the “right” choices5? Many researchers
Example questions from an assessment of basic numerical understanding
already recognised a long time ago: In 1937, an editorial in
and policy makers do. I strongly disagree. Instead, we need
on nationally representative samples in the United States of America and
U.S. Adults German Adults
the Lancet2, one of the leading medical journals, noted about
understandable information for at least three reasons:
Germany, and the proportions who answered correctly (adapted from 3). ages 25-69 ages 25-69 Figure 1. When the British press announced in October 1995 that the third generation of oral contraceptive pills
In the Bingo Lottery, the chance of winning a $10 prize is 1%.
increases the risk of potentially life-threatening blood clots in the legs or lungs by 100%, a reversal of the downward
What is your best guess about how many people will win a
trend in abortions was subsequently observed (adapted from 10).
$10 prize if 1,000 people each buy a single ticket for Bingo Lottery? Answer: 10 person(s) out of 1,000
In the Daily Times Sweepstakes, the chance of winning a car is 1 in 1,000.
What percentage of tickets for the Daily Times Sweepstakes win a car?
Imagine that we flip a fair coin 1,000 times. What is your best guess about
how many times the coin will come up heads in 1,000 flips?
Which of the following numbers represents the biggest risk of
getting a disease? 1 in 100, 1 in 1,000, or 1 in 10?
Risk communication: Why we need
Not involving patients in important medical decisions is also
understandable information
ethically unjustifiable, as it is their health that is at stake.
It is premature to give up on people’s ability to
This is particularly important as patients and physicians do
understand health statistics. The example of the pill scare
not always have the same preferences, and not even the
above not only illustrates that health statistics can be
severely misunderstood, but also that the representationmatters. Had the absolute risk increase (“one more in
The recent increase in cases of progressive multifocal
7,000”) of the third generation pills been presented
leukoencephalopathy (PML) for people with MS who were
instead of the relative risk increase (“100%”), there
treated with natalizumab (Tysabri) exemplified those
Wolfgang Gaissmaier, Harding Center for Risk Literacy, Max Planck Institute for Human Development, Berlin, Germany
probably would not have been a pill scare at all (and
differences. It turned out that patients would accept a
higher risk of this extremely severe side effect than
physicians: While only 51% of physicians would accept an
Relative risks cannot only create fears. They are even
event rate of more than two in 10,000, 83% of patients
“In this world, nothing is certain except death and taxes”
statistics that they “afford one of the few examples in which the
more commonly used to make treatment effects look
would do so (Figure 2)8. (Note that the current estimate of
Benjamin Franklin already noted in 1789, on the eve of the
use (or abuse) of mathematical methods tends to induce a
bigger. An advertisement of Lipitor, for instance, hailed the
the actual event rate is about one in 1,000).
French Revolution. This ironic statement nicely illustrates that
strong emotional reaction in non-mathematical minds”. It
drug as cutting the risk of stroke by nearly half. In
everything in life is laden with risk and that we are constantly
complained that for “most of us figures impinge on an
absolute terms, however, the benefits were rather small,
Many of the more cautious physicians probably had
at the mercy of this uncertainty. Even nowadays, however,
educational blind spot” – even for physicians. And it still holds
as after four years, 2.8% of patients taking placebo had a
the best interest of their patients in mind, but some also may
people are uneasy about uncertainty, and many anxiously
true today that big parts of the population have difficulties in
have had defensive reasons as they could be afraid
strive towards a certainty that does not exist. Yet society
understanding numerical information – there is collective
to be held responsible if severe side effects occurred.
needs people who learn to cope with risks and deal with
statistical illiteracy, as a few examples in Table 1 illustrate3.
Many studies show that people, patients as well as
At least in other medical domains, such as prostate cancer
them in an informed way. The general lack of training to deal
physicians, understand the statistical information much
screening, it is well documented that there are many
with risks in today’s technological society has become a
In recent years, an effort has been made to involve patients
better when they are presented as absolute risks than as
physicians who would recommend screening although they
problem, as the following example illustrates:
more strongly by sharing medical decisions between physicians
relative risks6. Difficulties in understanding statistical
do not believe in its effectiveness, often for legal reasons9.
and patients. Yet statistical illiteracy poses a severe obstacle for
information about health should not only be looked for in
When the British press announced in October 1995 that
shared decision making, which relies on the exchange of
our mind and our genes. Rather, the same information can
the third generation of oral contraceptive pills increase
information between the physician and the patient and the
either be represented in a nontransparent format to create
the risk of potentially life-threatening blood clots in the
involvement of both patient and physician in making the
confusion, fear or undue enthusiasm about a particular
legs or lungs by 100%, many women reacted with fear
decision. This requires that both patients and doctors
drug, or it can be transparently represented to foster
and decided not to take this pill anymore. This ‘pill scare’
understand the benefits and harms of different treatment
insight. Numerous methods have already been developed
led to an estimated 13,000 additional abortions in the
options. A risk communication based on misunderstandings,
to convey quantitative information effectively, including a
following year, increasing the cost for the National Health
however, renders the “informed” in informed shared decision
variety of graphical representations7. Service for abortion provision by about £4 to 6 million (Figure 1)1. But what did the increase by 100% actually mean? The studies on which the warning was based had
Should one thus conclude that patients are not, and probably
shown that the absolute risk had increased from one to
never will be, able to evaluate health benefits and risks
two out of every 7,000 women.
accurately? And that, as a consequence, there is a need for abenevolent paternalism that uses methods of propaganda to
The example illustrates a problem in the communication of
persuade them to do what is considered best for them, or by
% Correct answer
statistical information about health, and this problem was
nudging them to make the “right” choices5? Many researchers
Example questions from an assessment of basic numerical understanding
already recognised a long time ago: In 1937, an editorial in
and policy makers do. I strongly disagree. Instead, we need
on nationally representative samples in the United States of America and
U.S. Adults German Adults
the Lancet2, one of the leading medical journals, noted about
understandable information for at least three reasons:
Germany, and the proportions who answered correctly (adapted from 3). ages 25-69 ages 25-69 Figure 1. When the British press announced in October 1995 that the third generation of oral contraceptive pills
In the Bingo Lottery, the chance of winning a $10 prize is 1%.
increases the risk of potentially life-threatening blood clots in the legs or lungs by 100%, a reversal of the downward
What is your best guess about how many people will win a
trend in abortions was subsequently observed (adapted from 10).
$10 prize if 1,000 people each buy a single ticket for Bingo Lottery? Answer: 10 person(s) out of 1,000
In the Daily Times Sweepstakes, the chance of winning a car is 1 in 1,000.
What percentage of tickets for the Daily Times Sweepstakes win a car?
Imagine that we flip a fair coin 1,000 times. What is your best guess about
how many times the coin will come up heads in 1,000 flips?
Which of the following numbers represents the biggest risk of
getting a disease? 1 in 100, 1 in 1,000, or 1 in 10?
At the beginning of the 21st century, nearly everyone inindustrial societies has been taught reading and writing,but not statistical thinking. Many researchers present the
Information news
Finally, patients need to be well-informed, becausephysicians may not understand health statistics
problem of statistical illiteracy as if it were largely a
themselves and therefore unintentionally misinform them.
consequence of cognitive limitations13. In contrast to this
For instance, many gynaecologists believe that 80% or
internal view, the majority of causes for statistical illiteracy
90% of women who receive a positive mammogram in
discussed here can be found in the external environment,
breast cancer screening actually have cancer10. However,
such as in nontransparent reporting of the health related
the true figure is only about 10%, as most positive
information. A major remedy therefore would be to
provide transparent health information based on the bestavailable clinical evidence to the public, and Sascha
Again, the reasons for this lack of understanding needs to be
Köpke and Christoph Heesen have presented excellent
looked for in the physicians’ environment. Even many of the
examples of how this can be achieved in MS in a recent
leading medical journals, such as the BMJ, JAMA or The
issue of Way Ahead14. Additionally, the public needs to be
n Website. The MS Trust website is regularly updated by
taught how to deal with risk and uncertainty so that they
the information team. The site provides a range of
Lancet, report the clinical evidence in a misleading way thatmakes the results look more favourable. A particularly
are able to ask the right questions and to know when they
misleading way is called mismatched framing, which consists
are being misled. As Gerd Gigerenzer and Muir Gray put it
of reporting the benefits as relative risks (big numbers) and
in a timely manifesto - Better doctors, better patients,
Living with MSwww.mstrust.org.uk/information
the side effects as absolute risks (small numbers)11. better decisions: Envisioning health care 202015:
• Discussions on personal experiences of MS, such
“The 20th century became the century of the doctor,
Provide free evidence based health information for the clinics, and the medical industry.”
Already in the 1930s, HG Wells12 predicted that for an
• Themed chatrooms allowing people with MS to
discuss subject issues with health professionals
educated citizenship in a modern democracy, statistical
“The 21st century should become the century of
Providing up-to-date Information and Research
and others in a similar situation. Our next chatroom
thinking would be as indispensable as reading and writing.
the patient.”
. Patients are willing to accept higher risks of progressive multifocal leukoencephalopathy (PML) when treated with
Supplying latest information on research and
The information team can be contacted by telephone
key areas of MS, such as publications, the
natalizumab (Tysabri) than physicians. The figure shows the risk at which patients would stop taking the drug, and at which
(Freephone 0800 032 3839 or 01462 476700), or by
physicians would stop prescribing it (adapted from 8).
writing to us via post or email (details are on the back
n Enquiry Service: The MS Trust offers a free telephone
enquiry service for people with MS - Freephone
The personal enquiry service is for anyone affected
by MS such as people with MS, their families and
friends, health professionals and more. Questions can
Although sexual issues are not unusual for men with
include a wide range of issue about MS such as
MS, the effect of MS on sexuality can sometimes be a
symptomatic treatment options or the location of the
difficult topic for men with MS to talk about.
nearest MS nurse. MS related literature searches or
information on research news reported in the press
Studies estimate that more than half of men with
MS will be affected by difficulty with erections,
orgasms or having satisfying sex to a certain degree
Newsletters. In addition to producing information and
at some time, regardless of whether someone is
research updates, news alerts for health professionals
straight, gay or bi and whether part of a couple or
and Way Ahead, we compile Open Door. Open Door is
single. Sexuality is an important part of life and
a quarterly newsletter, designed to interest both people
factors that affect this, whether physical or emotional,
living with MS, friends, family and carers, but will also
Risk at which one would stop natalizumab treatment
be of interest to health professionals and covers
References
reports about the world of MS, recent research news
Drawing on input from health professionals and
and information on the activities of the MS Trust.
1. Furedi A. The public health implications of the 1995 “pill scare.” Hum
illustrated by quotes from men who live with sexual
9. Steurer J, Held U, Schmidt M, et al. Legal concerns trigger prostate-specific
antigen testing. J Eval Clin Pract 2009;15:390-2
n Books and factsheets. The information team publishes
issues, Sex and MS explores the causes and
2. Mathematics and medicine. Lancet 1937:229:31.
10. Gigerenzer G, Gaissmaier W, Kurz-Milcke E, et al. Helping doctors and patients
and provides access to an increasing range of books
management options for difficulty with desire, arousal
3. Galesic M, Garcia-Retamero R. Statistical numeracy for health: A cross-cultural
make sense of health statistics. Psychol Sci Public Interest 2007;8:53-96.
and climax. It also considers the partner's perspective
comparison with probabilistic national samples. Arch Intern Med 2010;170:462-8
11. Sedrakyan A, Shih C. Improving depiction of benefits and harms: analyses of
covering various aspects of MS, which we hope that
and issues around talking about sexual issues.
4. Gaissmaier W, Gigerenzer G. Statistical illiteracy undermines informed shared
studies of well-known therapeutics and review of high-impact medical journals.
people involved with MS will find of value. Many
decision making. Z Evid Fortbild Qual Gesundh.wesen 2008;102:411-3.
publications are written in partnership with experienced
By raising awareness of the support that is available and
5. Thaler RH, Sunstein CR. Nudge: improving decisions about health, wealth, and
12. Wells HG. World brain. London: Cambridge University Press; 1994 (Original
health professionals and with members of our readers'
happiness: Yale University Press; 2008.
ways of managing difficulties that may occur, the book
panel (people with MS) to ensure the publication is
6. Covey J. A meta-analysis of the effects of presenting treatment benefits in
13. Tversky A, Kahneman D. Judgement under uncertainty: heuristics and biases.
shows that it is not necessary to struggle in silence.
different formats. Med Dec Making 2007;27:638-54.
meeting the needs of the intended readers. Factsheets
7. Fagerlin A, Ubel PA, Smith DM, et al. Making numbers matter: Present
14. Köpke S, Heesen, C. Engaging people with MS in decision-making. The
are also produced which are intended to give a good,
A copy of Sex and MS: a guide for men can be
and future research in risk communication. Am J Health Behav 2007;31
concept of evidence-based patient information. Way Ahead 2010;14(4):6-9.
up-to-date, basic introduction to key issues of MS such
ordered from the back page of this issue or via the
15. Gigerenzer G, Gray M. Launching the century of the patient. In: Gigerenzer G,
as specific symptoms, available treatments, and other
8. Heesen C, Kleiter I, Nguyen F, et al. Risk perceptions in natalizumab-treated
Gray M, editors. Better doctors, better patients, better decisions: Envisioning
multiple sclerosis patients and their neurologists. Mult Scler 2010;16:1507-12.
health care 2020. Cambridge: MIT Press; 2011. p. 3-28.
Depression: Symptoms and Treatment Patient Education Handout associated with UMHS Clinical Care Guideline This information is not a tool for self-diagnosis or a substitute for medical treatment. You should speak to your health-care provider or make an appointment to be seen if you have questions or concerns about this information or your medical condition. What is depression? Depress
Risk Analysis of Insecticide Residues Detected on Fresh Produce on Guam Prepared by Dr. Aubrey Moore, University of Guam Extension Entomologist / Guam Pesticide Safety Education Program Coordinator October 27, 2009 The Division of Environmental Health of the Guam Department of Public Health and Social Services (DPSS) collected samples of fresh produce from a fresh vegetable stand o