Psychology vs Organizations in Organ Procurement

by Kieran Healy on April 9, 2008

Via Sally Satel, here’s a bit from a Freakonomics discussion. Stephen Dubner asked a bunch of people, “How much progress have psychology and psychiatry really made in the last century?” One of the respondents, Dan Ariely (a Professor of Management at MIT) cites some work about organ donation (emphasis added):

One of my favorite graphs in all of social science is the following plot from an inspiring paper by Eric Johnson and Daniel Goldstein. This graph shows the percentage of people, across different European countries, who are willing to donate their organs after they pass away. When people see this plot and try to speculate about the cause for the differences between the countries that donate a lot (in blue) and the countries that donate little (in orange) they usually come up with “big” reasons such as religion, culture, etc. But you will notice that pairs of similar countries have very different levels of organ donations.

For example, take the following pairs of countries: Denmark and Sweden; the Netherlands and Belgium; Austria and Germany; and (depending on your individual perspective) France and the U.K. These are countries that we usually think of as rather similar in terms of culture, religion, etc., yet their levels of organ donations are very different.

So, what could explain these differences? It turns out that it is the design of the form at the D.M.V. In countries where the form is set as “opt-in” (check this box if you want to participate in the organ donation program) people do not check the box and as a consequence they do not become a part of the program. In countries where the form is set as “opt-out” (check this box if you don’t want to participate in the organ donation program) people also do not check the box and are automatically enrolled in the program. In both cases large proportions of people simply adopt the default option.

You might think that people do this because they don’t care — that the decision about donating their organs is so trivial that they can’t be bothered to lift up the pencil and check the box. But in fact the opposite is true. … The organ donation issue is just one example of the influence of rather “small” changes in the environment (opt-in vs. opt-out) on our decisions.

Johnson and Goldstein’s work on the role of default options in decision-making is good, but the figure above (especially with its y-axis labeled “Effective Consent Percentage”) is misleading as presented by Ariely. First he says, correctly, that the data show “the percentage of people, across different European countries, who are willing to donate their organs after they pass away.” But then he says, wrongly, that “similar countries have very different levels of organ donations.” The graph shows the number of people who say they are willing in principle to be donors, and the large difference that the default option to this question makes. The casual reader might think—as Ariely himself seems to—that the actual rate of organ procurement in those presumed-consent countries is vastly higher than that in informed-consent countries. But this is not the case at all. The figure shows is how many people sign up given the defaults (opt-in vs opt-out), and not the rate of actual organ donors procured.

Here is a figure showing the organ procurement rate for various presumed- and informed-consent countries from the early 1990s to 2002 or so. Each green circle is the procurement rate for a particular country-year. (I want to focus on average differences between countries so I don’t show the time series itself. Click here for a figure showing the time trends.)

You can see that there are differences in the procurement rate between presumed- and informed-consent countries, and the highest-performing presumed-consent countries on average (Spain, Austria) score higher than the highest-performing informed consent countries. But the differences are not that big, and they are probably due mostly other features of the procurement system in the presumed consent countries. There is certainly not the huge disparity you might believe exists from a quick look at the post on the Freakonomics blog . (Incidentally, all of the countries shown here had their legal regime set as presumed- or informed-consent before the period covered by the data, so the often large within-country variability can’t be explained by the opt-in or opt-out defaults. Italy’s procurement rate, for instance, grew rapidly in the 1990s with no change in the law.)

In fact, as I’ve discussed recently in this post and argue in this paper, it is not at all clear that consent laws per se have any strong effect on the procurement rate (as distinct from their effect on people’s attitudes). Even if most people support organ donation, there are still large logistical hurdles to be overcome at the point of procurement. It is investment in the procurement infrastructure that really makes the difference to rates of organ donation, even if default options to opt-in or opt-out have large effects on people’s professed willingness to participate in the system.

Update: John Graves at the IQSS Blog makes the same error. As always, it is striking how easy it is for a mistake like this to propagate.

{ 14 comments }

1

mkl 04.09.08 at 9:45 pm

Denmark’s acheiving a procurement rate more than 3x the consent rate makes one wonders what the point of consent is. What is the denominator to the procurement rate?

2

Kieran Healy 04.09.08 at 9:47 pm

Per million population. Not ideal, but the best one can do cross-nationally. The number in the Defaults chart is probably not calculated in terms of the overall population but rather vis a vis the number of people given the opportunity to check the box (or not).

3

engels 04.09.08 at 9:58 pm

…France and the U.K. These are countries that we usually think of as rather similar in terms of culture…

I think most of your French readers have just walked away in disgust. (Not that I blame them.)

4

mkl 04.09.08 at 10:00 pm

Oughtn’t the denominator to the procurement rate be the number of deaths, perhaps just those deaths where organs are recoverable? If the Spaniards are extracting the organs of 35% of the population, I’m definitely changing my holiday plans… of course, that would explain why their housing market’s in a bit of a mess.

5

mkl 04.09.08 at 10:05 pm

er, actual donors per million population. Got it.
Never mind.

6

Kieran Healy 04.09.08 at 10:09 pm

Oughtn’t the denominator to the procurement rate be the number of deaths, perhaps just those deaths where organs are recoverable?

Yes. In my book and some papers on this stuff I do an analysis for the U.S. case using the best available estimate of donor-evaluable deaths — that subset of all deaths where the cause and circumstance of death are consistent with the possibility of organ procurement. But in practice this number is very difficult to calculate and get a consistent time series on, even just for the United States. (A report from a while ago on this topic by the GAO found that the accurate collection of this kind of data at a national level would be too expensive, even for the Federal Government.)

As it turns out, at least in my experience the use of donor evaluable deaths vs all deaths vs the total population turns out not to make a very large difference to quantitative estimates of interest. (Which, I can tell you, was a little irritating to discover as a grad student, after I had gone to considerable trouble to calculate the in-principle better number. There is a lesson here.)

7

Aaron Swartz 04.09.08 at 10:10 pm

Kieran, this obsessive focus on facts is exactly why you will never be a popular freakonomist.

8

Kieran Healy 04.09.08 at 10:13 pm

I know, I know.

9

CK 04.09.08 at 10:46 pm

In a recent LA Times op-ed describing their proposed “libertarian paternalism” movement, Sunstein and Thaler also draw on Johnson and Goldstein:

If we want to increase the supply of transplant organs in the United States, we could presume that people want to donate, rather than treating nondonation as the default. A study by social scientists Eric Johnson and Dan Goldstein showed that “presumed consent” could save thousands of lives annually.

Sounds like they’re reading even more into the study than Ariely does. Given your research, and your description of Johnson and Goldstein, it seems that Sunstein and Thaler’s claim is pretty indefensible.

10

Anthony 04.09.08 at 11:37 pm

The one thing which jumps out of the first set of data is that the Swedes are selfish bastards about their organs. They’ve got a 15% rate of actively declining consent, while most of the rest have less than 2%.

11

Bruce Baugh 04.10.08 at 4:02 am

A freakonomics claim proves to abuse selected data and ignore everything else in favor of a pat conclusion? I am shocked, shocked to find that there’s freakaonomics here.

12

KCinDC 04.10.08 at 4:08 am

I noticed that too, Anthony. Do the Swedes have something wrong with their question wording? Are there Swedish-only rumors about doctors killing patients to get their organs?

13

Kieran Healy 04.10.08 at 4:23 am

The one thing which jumps out of the first set of data is that the Swedes are selfish bastards about their organs. They’ve got a 15% rate of actively declining consent, while most of the rest have less than 2%.

Here’s what I think it happening. When you run an Opt-In or Opt-Out system, you will have a donor registry with the names of those people who have opted in or opted out as appropriate. A number of Presumed-Consent countries have _only_ an Opt-Out registry. I don’t have data for Portugal, Hungary or Poland. But France and Austria are like this, having no opt-in registry, just an opt-out one. Belgium has two registries, but its presumed-consent system is unusually strong. But Sweden has both an Opt-In and an Opt-Out registry. This presumably makes the choice situation more complicated and default-action type arguments wouldn’t be expected to apply so easily. So I think this may explain why Sweden has a lower rate of sign-up to be an organ donor than other presumed-consent countries — there’s more opportunity for choice at the point of decision, hence it’s easier not to sign up.

14

Sortition 04.10.08 at 5:38 am

It would be interesting to see what would be the opt-in and opt-out rates in a “neutral” setup where you have to check one of two boxes. I guess the boxes would have to be randomly ordered to eliminate potential bias. Does no country have this arrangement?

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