"You can put social innovation to the same rigorous, scientific tests that we use for drugs. And in this way, you can take the guesswork out of policy-making by knowing what works, what doesn't work and why. And I'll give you some examples with those three questions.
"As you have to come back, and you are so busy and you have so many other things to do, you will always tend to postpone and postpone, and eventually it gets too late. Well, if that's the problem, then that's much easier. Because A, we can make it easy, and B, we can maybe give people a reason to act today, rather than wait till tomorrow
"You make it easy and give a reason to act now by adding a kilo of lentils for each immunisation. Now, a kilo of lentils is tiny. It's never going to convince anybody to do something that they don't want to do. On the other hand, if your problem is you tend to postpone, then it might give you a reason to act today rather than later.
"So what do we find? Well, beforehand, everything is the same. That's the beauty of randomisation. Afterwards, the camp -- just having the camp -- increases immunisation from six percent to 17 percent. That's full immunisation. That's not bad, that's a good improvement. Add the lentils and you reach to 38 percent.
"Now, you might say, "Well, but it's not sustainable. We cannot keep giving lentils to people." Well, it turns out it's wrong economics, because it is cheaper to give lentils than not to give them. Since you have to pay for the nurse anyway, the cost per immunisation ends up being cheaper if you give incentives than if you don't."