What drives people to become an organ donor?

Illustration by Johanna Henry

Default option as a means to nudge people toward consenting to organ donation

Choice architecture is an approach that emphasizes that there are many ways in which choices can be presented to the decision-maker, and aims to use small  nudges to help people toward certain choices or options (Johnson et al., 2012). One way choice architects can influence people’s decisions is by presenting choices in a certain way, like selecting a default option.

Before going into a deeper explanation of what a default option is, let’s take a look at the concept of “nudging”. A nudge is a simple aspect that influences people’s behavior in a predictable way, without prohibiting any choices, or significantly changing the economic incentives. For example, if a school wants to reduce the amount of candy bars that students eat, then placing fresh fruits instead of candy bars near the register in the cafeteria would be considered as a nudge, while banning candy bars outright does not constitute a nudge. There are several types of nudges, but in this article, I will focus on the default option nudge.

A default option is an option that becomes effective when no active choice is made (Vetter & Kutzner, 2016), by influencing individuals who accept whatever the default setting is, even if it has significant consequences (Kaiser et al., 2014). The default option nudge can be applied to a variety of contexts, like consumer choices, health-related decisions, or environmental policies. Now let’s get concrete.  

Johnson and Goldstein (2003) asked the question “What drives the decision to become a potential organ donor?”. Within the American population, they had found a gap between people who approve of organ donation (85%) and those who themselves agreed to be a donor by signing a donor card (28%). Within the European Union, the donation rates vary a lot between countries. This is seemingly independent of organ donation infrastructure, economic and educational status, and religion (Gimbel et al. in Johnson & Goldstein, 2003). The authors explain the differences in donation rates between the countries by referring to the local organ donation policy. More precisely, the choice between an opt-in policy (meaning that no one is an organ donor unless they register to be one), and an opt-out policy (meaning that everyone is a donor unless they request not to be) (Johnson & Goldstein, 2003). The opt-out constitutes a default option nudge to be an organ donor. By the way, in Switzerland, a proposal to change to an opt-out policy will be put on vote the 15th of May 2022!

Figure 1: Johnson & Goldstein (2003)

As you can see on the histogram, the gap in consent rates is huge depending on public policies in the countries in question. For those waiting in line to receive a new organ, increasing the number of donors is a matter of life and death. 

But how does the default option influence choices?
There are three main explanations in the literature. First, default options can be perceived as indicators of the recommended action, a suggestion by policy-makers (Johnson & Goldstein, 2003; Vetter & Kutzner, 2016; Kaiser et al., 2014). This is linked to social influence: the default option is perceived as an injunctive norm and as the option that most people choose (Everett et al., 2015), so choosing the non-default option implies a departure of the majority group (Kaiser et al., 2014). Secondly, making a decision demands an effort, whereas accepting a default option doesn’t (Johnson & Goldstein, 2003; Vetter & Kutzner, 2016; Kaiser et al., 2014). In the case of an opt-out option, having to fill out a form to request not to be an organ donor can be unpleasant and thus increase acceptance of the default. Third, it is likely that some choose the default option simply to “go with the flow” and as a way to avoid making an active decision. 

In the end, the default option will be chosen more often than other options. However, the default option doesn’t work in any situation of course: making it more difficult to reach candy than fruits in your kitchen probably won’t  stop your children from preferring candy to fruit. 


Everett, J. A. C., Caviola, L., Kahane, G., Savulescu, J., & Faber, N. S. (2015). Doing good by doing nothing? The role of social norms in explaining default effects in altruistic contexts. European Journal of Social Psychology, 45(2), 230‑241.

Johnson, E. J., & Goldstein, D. (2003). Do Defaults Save Lives?

Johnson, E. J., Shu, S. B., Dellaert, B. G. C., Fox, C., Goldstein, D. G., Häubl, G., Larrick, R. P., Payne, J. W., Peters, E., Schkade, D., Wansink, B., & Weber, E. U. (2012). Beyond nudges : Tools of a choice architecture. Marketing Letters, 23(2), 487‑504.

Kaiser, F. G., Arnold, O., & Otto, S. (2014). Attitudes and Defaults Save Lives and Protect the Environment Jointly and Compensatorily : Understanding the Behavioral Efficacy of Nudges and Other Structural Interventions. Behavioral Sciences, 4(3), 202‑212.

Vetter, M., & Kutzner, F. (2016). Nudge me if you can—How defaults and attitude strength interact to change behavior. Comprehensive Results in Social Psychology, 1(1‑3), 8‑34.