Nudge Me! A field experiment on reminders for medication adherence

Reminders are widely used in public policy to promote beneficial behaviors, but little is known about how individuals value them. We conduct a field experiment with over 4,000 pregnant women in South Africa, delivered via the national mobile health platform, to assess how different reminder types—purely attentional, informational, and morally persuasive—affect both adherence to iron supplementation and willingness to pay (WTP) for future reminders. Despite high self-reported adherence, demand for reminders is substantial: over 80% choose additional reminders when free, and many are willing to pay to receive them. Exposure to reminders increases both adherence and WTP. However, reminders that include additional health information significantly reduce both outcomes relative to simple reminders, showing that even well-intended information can have unintended consequences. Our results can help inform the design of public health communications.