Behavioural nudges increase COVID-19 vaccinations

Hengchen Dai,Shital Pandya,Hardikkumar Modi,Sitaram Vangala,Lily Roh,Daniel M Croymans,Naveen Raja,Maria A Han,Michael Sloyan,Silvia Saccardo

doi:10.1038/s41586-021-03843-2

Abstract

Enhancing vaccine uptake is a critical public health challenge1. Overcoming vaccine hesitancy2,3 and failure to follow through on vaccination intentions3 requires effective communication strategies3,4. Here we present two sequential randomized controlled trials to test the effect of behavioural interventions on the uptake of COVID-19 vaccines. We designed text-based reminders that make vaccination salient and easy, and delivered them to participants drawn from a healthcare system one day (first randomized controlled trial) (n = 93,354 participants; clinicaltrials number NCT04800965) and eight days (second randomized controlled trial) (n = 67,092 individuals; clinicaltrials number NCT04801524) after they received a notification of vaccine eligibility. The first reminder boosted appointment and vaccination rates within the healthcare system by 6.07 (84%) and 3.57 (26%) percentage points, respectively; the second reminder increased those outcomes by 1.65 and 1.06 percentage points, respectively. The first reminder had a greater effect when it was designed to make participants feel ownership of the vaccine dose. However, we found no evidence that combining the first reminder with a video-based information intervention designed to address vaccine hesitancy heightened its effect. We performed online studies (n = 3,181 participants) to examine vaccination intentions, which revealed patterns that diverged from those of the first randomized controlled trial; this underscores the importance of pilot-testing interventions in the field. Our findings inform the design of behavioural nudges for promoting health decisions5, and highlight the value of making vaccination easy and inducing feelings of ownership over vaccines.

Highlights

These approaches could help to increase vaccination rates in the context of the current COVID-19 pandemic[12], which has had unprecedented costs[13]
Participants (132,337) who had not made the rst-dose appointment at UCLA Health or obtained the rst dose anywhere in California by the end of day t were enrolled in the rst randomized controlled trials (RCTs) by 23 February 2021
In contrast to the patterns observed in the first RCT, the video intervention resulted in a small—but statistically significant—increase in people’s self-reported interest in getting the vaccine; we found no evidence that adding ownership language increased vaccination intentions (Extended Data Table 5)

Summary

Introduction

These approaches could help to increase vaccination rates in the context of the current COVID-19 pandemic[12], which has had unprecedented costs[13]. It is critical to understand how to best design behavioural interventions to boost intentions to get vaccinated, remove barriers to following through on good intentions or both[3]. We report data from two sequential large-scale randomized controlled trials (RCTs) that investigate whether nudging people to get vaccinated, using reminders that are carefully designed to reduce barriers to following through, can improve the uptake of COVID-19 vaccines. Participants (102,675) who had not made the rst-dose appointment at UCLA Health or obtained the rst dose anywhere in California (as far as UCLA Health could tell) by the end of day t + 8 were enrolled in the second RCT by 23 February 2021

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Methods

Findings

Conclusion