Since You Asked

The ins and outs of organ donation

If we automatically put people on the donor register we’d presumably see more transplants

‘NHS achieves ground-breaking 50% increase in deceased organ donors’
National Health Service press release, April 11

That’s good news.

Absolutely – although about 1,000 people a year die waiting for an organ. Half of those who receive kidneys wait more than three years, and being on dialysis is not fun. So we need to do more. And it turns out that economists are experts on allocating scarce resources.

You are about to propose a market for human organs?

No, I think we can agree that the idea of a market for live kidney donations is a non-starter. Except in Iran.


Yes, buying kidneys is legal in Iran. Can we move on? Proposal number two is to establish a different way to exchange kidneys. The idea is simple: many patients have friends, spouses or siblings who are willing to donate a kidney but cannot because of incompatible tissue or blood types. In 1986 Felix Rapaport, a leading transplant surgeon, floated the idea of putting together patients and donors to allow each donor to give a compatible kidney to the other donor’s loved one. Even now the idea is called “paired donation” because “exchange” might sound too much like a market.

But surely nobody could object to such a thing.

It has caught on and been made more effective by the efforts of economists such as Al Roth, a recent Nobel laureate based at Stanford University. They have designed algorithms to maximise the number of successful transplants. Another idea, the brainchild of a surgeon, Michael Rees of the University of Toledo, is to set up long chains of donations, beginning with a single altruist who is willing to donate a kidney to a stranger without needing to enter some sort of paired donation arrangement.

Are such schemes making their way over to the UK?

They are indeed; we have several kidney sharing schemes here. But they are small compared with the number of people waiting for kidneys. And it is not so easy for a living donor to offer a heart or a lung.

Any other brilliant economic ideas?

Here’s a curious observation, from a 2003 paper written by the behavioural scientists Eric Johnson and Daniel Goldstein: in countries where people must opt out if they don’t want to donate their organs, “consent” rates are typically close to 100 per cent. In countries such as the UK, where people must opt in to become donors, consent rates are much lower. This leads to the natural observation that if we just automatically put people on the donor register unless told otherwise, we’d see more organ transplants and more lives transformed. Wales looks likely to adopt this position.

And rightly so, I’d say. Thank goodness for behavioural economics.

Not so hasty. It’s not at all clear that presumed consent would help. Many deceased donors were never on the register and many people on the register end up not being donors. One of the reasons why more transplants are taking place is because the NHS is getting more competent – and has clearer legal authority – at making sure they happen. This means identifying donors, persuading families to give consent and even performing procedures on patients who are not yet dead.

So a lot of this is actually about medical practice and bureaucratic efficiency?

Of course it is. And what families feel about it is also important. If we fill our donor registry with auto-enrolled donors, will that really persuade distraught families to support transplants? In any case, behavioural economics suggests a more elegant alternative.

Do tell.

Prof Johnson and Dr Goldstein are often cited in favour of presumed consent. But they also discovered that if you demand a yes or no answer, most people willingly join the register. You don’t need to sneak them on to it by default: you can just request that they express a preference. Since July 2011, people applying for driving licences in the UK have been faced with just this choice. The majority of new donors now arrive on the register in this way, although disappointingly the “not now” answers outnumber the “yes” or “already registered” answers by more than two to one. But, encouragingly, a new trial will be experimenting with different prompts, words and images with the aim of discovering what approach works best. That’s good. When doctors and nurses are trying to win approval from grieving families, it will be far more helpful if people are registered donors by choice, not by default.

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13th of April, 2013Since You Asked • Comments off