POLICY FORUM
Governments, companies, and publicagencies inadvertently run “natural experiments” testing the power of defaults.
Studies of insurance choice (20), selectionof Internet privacy policies (21, 22), andthe level of pension savings (23) all show
large effects, often with substantial financial consequences.

MEDICINEDo Defaults Save Lives?
1009080
7060
50
40
30
20101338

79

Opt-Out

Neutral0Opt-In

Effective consent rates, online experiment,
as a function of default.

preferences for being an organ donor areconstructed, defaults can influence choicesin three ways: First, decision-makers might
believe that defaults are suggestions by thepolicy-maker, which imply a recommendedaction. Second, making a decision often involves effort, whereas accepting the default
is effortless. Many people would rather
avoid making an active decision about donation, because it can be unpleasant and stressful (17). Physical effort such as filling out aform may also increase acceptance of the default (18). Finally, defaults often represent
the existing state or status quo, and change
usually involves a trade-off. Psychologists
have shown that losses loom larger than theequivalent gains, a phenomenon known as
loss aversion (19). Thus, changes in the default may result in a change of choice.
99.98

10090
80

Defaults and Organ Donations
We investigated the effect of defaults on
donation agreement rates in three studies.
The first used an online experiment (24):161 respondents were asked whether theywould be donors on the basis of one ofthree questions with varying defaults. In
the opt-in condition, participants were toldto assume that they had just moved to a
new state where the default was not to be
an organ donor, and they were given achoice to confirm or change that status.
The opt-out condition was identical, except
the default was to be a donor. The third,
neutral condition simply required them tochoose with no prior default. Respondents
could at a mouse click change their choice,largely eliminating effort explanations.
The form of the question had a dramatic impact (see figure, left): Revealed donation rates were about twice as high when
opting-out as when opting-in. The opt-outcondition did not differ significantly fromthe neutral condition (without a default option). Only the opt-in condition, the current
practice in the United States, was significantly lower.
In the last two decades, a number ofEuropean countries have had opt-in or optout default options for individuals’ decisions to become organ donors. Actual decisions about organ donation may be affectedby governmental educational programs, the98

99.91

99.97

99.5

99.64
85.9

70
60
50
40
27.5

30
20

12

SwedenPortugal

PolandHungary

FranceBelgium

Austria

Germany

United Kingdom

4.25
Netherlands10017.17

The authors are at the Center for Decision Sciences,Columbia University, New York, NY 10027, USA.
*To whom all correspondence should be addressed:
ejj3@columbia.edu

82

42DenmarkS

Effective consent percentage

ince 1995, more than 45,000 people in
the United States have died waiting
for a suitable donor organ. Although
an oft-cited poll (1) showed that 85% ofAmericans approve of organ donation, lessthan half had made a decision about donating, and fewer still (28%) had granted permission by signing a donor card, a patternalso observed in Germany, Spain, andSweden (2–4). Given the shortage ofdonors, the gap between approval and action is a matter of life and death.
What drives the decision to become apotential donor? Within the EuropeanUnion, donation rates vary by nearly an order of magnitude across countries and thesedifferences are stable from year to year.
Even when controlling for variables such astransplant infrastructure, economic and educational status, and religion (5), large differences in donation rates persist. Why?
Most public policy choices have a noaction default, that is, a condition is imposed when an individual fails to make adecision (6, 7). In the case of organ donation, European countries have one of two
default policies. In presumed-consent
states, people are organ donors unless theyregister not to be, and in explicit-consent
countries, nobody is an organ donor without registering to be one.
According to a classical economics view,preferences exist and are available to the decision-maker—people simply find too little
value in organ donation. This view has led
to calls for the establishment of a regulated
market for the organs of the deceased (8, 9),
for the payment of donors or donors’ families (10, 11), and even for suggestions thatorgans should become public property upon
death (12). Calls for campaigns to change
public attitudes (13) are widespread. In classical economics, defaults should have a limited effect: when defaults are not consistent
with preferences, people would choose anappropriate alternative.
A different hypothesis arises from research depicting preferences as constructed,that is, not yet articulated in the minds ofthose who have not been asked (14–16). IfPercent consenting
to being donors

Eric J. Johnson* and Daniel Goldstein

Effective consent rates, by country. Explicit consent (opt-in, gold) and presumed consent (optout, blue).

21 NOVEMBER 2003

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POLICY FORUM

Donation rate per million

efforts of public health organizations, and serve as proxies for these constructs (5) andcultural and infrastructural factors. We ex- an indicator variable representing each year.
amined the rate of agreement to become aThis analysis presents a strong concludonor across European countries with ex- sion. Although there are no differences
plicit and presumed consent laws. We sup- across years, there is a strong effect of the deplemented the data reported in Gäbel (25) fault: When donation is the default, there is aby contacting the central registries for sever- 16.3% (P < 0.02) increase in donation, inal countries, which allowed us to estimate creasing the donor rate from 14.1 to 16.4
the effective consent rate, that is, the number million (see figure, this page, blue line).
of people who had opted in (in explicit-con- Using similar techniques, but looking only at
sent countries) or the number who had not 1999 for a broader set of European countries,opted out (in presumed-consent countries). including many more from Eastern Europe,
If preferences concerning organ donation Gimbel et al. (5) report an increase in theare strong, we would expect defaults to have rate from 10.8 to 16.9, a 56.5% increase (seelittle or no effect. However, as can be seen in figure, this page, red line). Differences in thethe figure (page 1338, bottom), defaults ap- estimates of size may be due to differences inpear to make a large difference: the four opt- the countries included in the analysis: Manyin countries (gold) had lower rates than the of the countries examined by Gimbel et al.
six opt-out countries (blue). The two distri- had much lower rates of donation.
butions have no overlap, and nearly 60 percentage points separate the two groups. One Conclusions
reason these results appear to be greater than How should policy-makers choose defaults?
those in our laboratory study is that the cost First, consider that every policy must have aof changing from the default is higher; it in- no-action default, and defaults impose physivolves filling out forms, making phone cal, cognitive, and, in the case of donation,
calls, and sending mail. These low rates of emotional costs on those who must change
agreement to become a donor come, in their status. As noted earlier, both nationalsome cases, despite
surveys and the no-de19
marked efforts to infault condition in our excrease donation rates. Inperiment suggest that17
the Netherlands, for exmost Americans favor
ample, the 1998 creorgan donation. This im15
ation of a national donor
plies that explicit conregistry was accompasent policies impose the13nied by an extensive edcosts of switching on theucational campaign andapparent majority (28).
11a mass mailing (of more
Second, note that dethan 12 million letters in
faults can lead to two
a country of 15.8 milkinds of misclassifica9
Opt-inOpt-outlion) asking citizens totion: willing donors
Default
register, which failed to
who are not identified
change the effective Estimated donation rate, opt-in versus or people who become
consent rate (26).
opt-out, as a function of default, donors against their
Do increases in 1991–2001. Means ± SEM; this paper, wishes. Balancing these
agreement rates result blue; Gimbel et al. (5), red.
errors with the goodin increased rates of dodone by the lives saved
nation? There are many reasons preventing through organ transplantation leads to deliregistered potential donors from actually cate ethical and psychological questions.
donating. These include: families’ objec- These decisions should be informed by furtions to a loved one’s consent, doctors’ hes- ther research examining the role of the threeitancy to use a default option, and a mis- causes of default effects. For example, onematch with potential recipients, as well as might draw different conclusions if the efdifferences in religion, culture, and infra- fect of defaults on donation rates is due pristructure.
marily to the physical costs of responding,
To examine this, we analyzed the actual than if they were due to loss aversion.
number of cadaveric donations made per
The tradeoff between errors of classifimillion on a slightly larger list of countries, cation and physical, cognitive, and emowith data from 1991 to 2001 (27). We ana- tional costs must be made with the knowllyzed these data using a multiple regression edge that defaults make a large difference
analysis with the actual donation rates as de- in lives saved through transplantation.
pendent measures and the default as a preOur data and those of Gimbel et al. sugdictor variable. To control for other differ- gest changes in defaults could increase doences in countries’ propensity to donate, nations in the United States of additionaltransplant infrastructure, educational level, thousands of donors a year. Because eachand religion, we included variables known to donor can be used for about three transwww.sciencemag.org

SCIENCEVOL 302

plants, the consequences are substantial in
lives saved. Our results stand in contrast
with the suggestion that defaults do notmatter (29). Policy-makers performing
analysis in this and other domains should
consider that defaults make a difference.
References and Notes
1. The Gallup Organization, “The American Public’sAttitude Toward Organ Donation and Transplantation” (Gallup Organization, Princeton, NJ,1993).
2. S. M. Gold, K. Shulz, U. Koch, The Organ Donation
Process: Causes of the Organ Shortage andApproaches to a Solution (Federal Center for Health
Education, Cologne, 2001),
3. H. Gäbel, H. N. Rehnqvist, Transplant. Proc. 29, 3093
(1997).
4. C. Conesa et al., , Transplant. Proc. 35,1276 (2003).
5. R. W. Gimbel, M. A. Strosberg, S. E. Lehrman, E.
Gefenas, F. Taft, Progr. Transplant. 13, 17 (2003).
6. R. H. Thaler, C. Sunstein, Univ. Chicago Law Rev., inpress.
7. C. Camerer, S. Issacharoff, G. Loewenstein, T.
O’Donoghue, M. Rabin, Univ. Penn. Law Rev. 151,2111 (2003).
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10. C. E. Harris, S. P. Alcorn, Issues Law Med. 3, 213 (2001).
11. D. Josefson, BMJ 324, 1541 (2002).
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13. J. S. Wolf, E. M. Servino, H. N. Nathan, Transplant. Proc.
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14. J. W. Payne, J. R. Bettman, E. J. Johnson, Annu. Rev.
Psychol. 43, 87 (1992).
15. P. Slovic, Am. Psychol. 50, 364 (1995).
16. D. Kahneman, A. Tversky, Eds., Choices, Values, andFrames (Cambridge Univ. Press, Cambridge, 2000).
17. J. Baron, I. Ritov, Org. Behav. Hum. Decision Processes
59, 475 (1994).
18. W. Samuelson, R. Zeckhauser, J. Risk Uncertainty 1, 7(1988).
19. A. Tversky, D. Kahneman, Q. J. Econ. 106(4), 1039
(1991).
20. E. J. Johnson, J. Hershey, J. Meszaros, H. Kunreuther, J.
Risk Uncertainty 7, 35 (1993).
21. S. Bellman, E. J. Johnson, G. L. Lohse, Commun. ACM(Assoc. Comput. Machin.) 44, 25 (February 2001).
22. E. J. Johnson, S. Bellman, G. L. Lohse, Marketing Lett.
13, 5 (February 2002).
23. B. C. Madrian, D. Shea, Q. J. Econ. 116(1), 1149 (2001).
24. Methods and details of analysis are available as supporting material on Science online.
25. H. Gäbel, “Donor and Non-Donor Registries in Europe”(on behalf of the committee of experts on theOrganizational Aspects of Co-operation in Organ
Transplantation of the Council of Europe, Brussels,
2002).
26. M. C. Oz et al., J. Heart Lung Transplant. 22, 389(2003).
27. We used a times series analysis to account for possible changes in transplant technology and infrastructure, as well as the effects of continuing public education campaigns.
28. An alternative advocated by the American Medical
Association (30) is mandated choice, which imposes
the cost of making an active decision on all. This practice is currently employed in the state of Virginia, but,consistent with the constructive preferences perspective, about 24% of the first million Virginians asked
said they were undecided (31).
29. A. L. Caplan, JAMA 272, 1708 (1994).
30. American Medical Association, “Strategies for cadaveric organ procurement: Mandated choice and presumed consent” (American Medical Association,Chicago, 1993).
31. A. C. Klassen, D. K. Klassen, Ann. Intern. Med. 125, 70(1996).
32. This research has been supported by the Columbia
University Center for Decision Science and theColumbia Business School Center for Excellence in EBusiness. We thank L. Roels for providing the data on
actual donation rates.
Supporting Online Materialwww.sciencemag.org/cgi/content/full/302/5649/1338/
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