Organ Donation: How 'Presumed Consent' and the Default Setting Change the Statistics

Organ donation is the most-cited example of how the default option can literally save lives. But it is also the one that shows where the power of the default ends.

The organ shortage and the price of the default decision

Transplant waiting lists are always longer than the number of donors. That is why even a small shift in the proportion of consenting people carries a high price — measured in lives saved.

The Johnson and Goldstein experiment

In the paper "Do Defaults Save Lives?" (Science, 2003), Eric Johnson and Daniel Goldstein demonstrated a sharp gap between opt-in and opt-out countries, one unexplained by differences in personal attitudes (Science). In their online experiment, a simple change of the default nearly doubled the share of consenters — from about 42% to 82% (Johnson & Goldstein, 2004).

The map of Europe: opt-in and opt-out

In opt-in countries (where one must actively register), effective consent stays low — from a few percent to about a quarter of the population. In opt-out countries (presumed consent, where one must actively refuse), consent often exceeds 90% (Science). The gap is explained not by beliefs but by inertia and the status of the default option.

Why consent ≠ transplants

An important caveat: legal "consent" does not equal actual transplants. The number of operations depends on infrastructure, the work of coordinators, and the role of the family, so the direct link between opt-out and a rise in donation is contested (Social Science & Medicine).

The crowding-out effect and criticism

Newer research points to a possible "crowding-out effect" on voluntary registration in the shift to opt-out, which complicates any clear-cut assessment (PNAS Nexus). The case remains contested: the power of the default is real, but presumed consent touches a person's body and will, and therefore demands particular ethical caution.