Nudge me! But don’t annoy me!

Nudging can be quite a powerful tool in communications from the health authorities to the general public, and it is, in effect, widely used in many parts of the world. Now a new study shows that it is very important to think about design method and understand your target audience, because subtle changes in design method can drastically alter recipient behaviour.  

Associate Professor Mette Trier Damgaard from the Department of Economics and Business Economics at Aarhus BSS, Aarhus University, together with Research Associate Kai Barron, WZB-Berlin, and Associate Professor Christina Gravert, Department of Economics at the University of Copenhagen, have studied how pregnant women in South Africa respond to different reminder designs. The results have been published in the Journal of Economic Behavior and Organization.

“We chose South Africa because it has a highly successful digital health platform called MomConnect aimed at pregnant women, and which covers more than 60% of all pregnancies in the country. Also, it is one of the largest health platforms of its kind globally,” explains Mette Trier Damgaard.

Iron supplements

The idea was to get the women to take iron supplements during pregnancy to avoid anaemia, which has negative effects both for the pregnant woman and for the unborn child. Anaemia is associated with a higher risk of stillbirth, premature birth and low birth weight.

The researchers examined three different types of nudges: A pure reminder to remember to take iron supplements, a reminder with additional information about the benefits of taking iron supplements and guidance on how to take the supplements for optimum effect, and a nudge, in which the mother makes a promise to her yet unborn child to take iron supplements.

Additional information, no thanks!

The effect of the three types of nudges was measured by the expectant mothers reporting whether they remembered to take the tablets. In addition, the value of the individual nudges for the women was measured by their willingness to pay to continue receiving reminders or to pay to avoid them.

“Rather surprisingly for us, we found that both the effect and the willingness to pay decreased significantly when reminders were supplemented with information about the use of iron supplements. The greatest effect and willingness to pay were seen for the pure reminders, while the promises to the unborn child were in between,” says Mette Trier Damgaard, who continues:

“Why this is so, we cannot say for sure. Perhaps you get annoyed at being sent information that you may already know, or it complicates things. What we can see is that the effect of and the demand for nudging decrease significantly when you add supplementary information and general guidance to pure reminders.”

High willingness to pay

After receiving the various nudges for some time, the demand for further pure reminders increased by 7.4 percentage points, while it declined by 6.1 percentage points if the reminders were supplemented with information.

The researchers generally saw a relatively high willingness among the pregnant women to pay for further reminders.

Just over 82% of the women wanted to receive further reminders, as long as it was free for them. The share increased to 95% when it was cheaper to receive the reminders than not to receive them. But even when they had to pay to receive the reminders, 40% of pregnant women were still willing to do so.

High level of compliance

Finally, the researchers found that the self-reported adherence to taking iron supplements increased by just 2–3 percentage points with pure reminders, while it decreased by 3.8 percentage points if supplementary information was provided.

“There’s already a high level of compliance with the guidance to take extra iron, so why do these women want reminders anyway?” asks Mette Trier Damgaard and comes up with two possible explanations.

“Perhaps the women exaggerate their self-reported adherence to the daily intake of iron because they want to demonstrate how good they are. We cannot rule this out, but at the same time we can see a relatively high willingness to pay, and it does not make sense to pay money just to show how good you are. Or maybe they report correctly, but the reminder simply makes life easier for them because they do not have to remember it themselves.”

New essential knowledge

According to the researchers, the study adds important new knowledge to our general understanding of the use of nudges and how we as humans are affected by them. The study shows that subtle differences in nudge design can make a huge difference.  

“We have previously shown that reminders can have a negative effect when it comes to donating to charity. In the current study with pregnant women, on the other hand, reminders have a very positive effect. In this case, it seems that adding information is a put-off,” says Mette Trier Damgaard and concludes:

“You have to think carefully about the design of nudges in each individual case. And you have to test the effect before you roll it out to the entire population.” 

Facts

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