Behavioral nudges increase COVID-19 vaccinations: Two randomized controlled trials

Abstract

Fighting the COVID-19 pandemic requires quick and effective strategies to maximize vaccine uptake. We present two sequential randomized controlled trials (RCTs) that tackle this challenge with behavioral science insights. We deliver text-based nudges to UCLA Health patients one day (first RCT; N=113,229) and eight days (second RCT; N=90,662) after they receive notifications of vaccine eligibility. In the first RCT, text messages designed to make vaccination salient and easy to schedule boost appointment and vaccination rates by 86% and 26%, respectively. Nudges that make patients feel endowed with the vaccine heighten these effects, but addressing vaccine hesitancy via a video-based information intervention does not yield benefits beyond simple text. These results hold across ethnicity and age groups. By contrast, online experiments (N=2,003) soliciting hypothetical responses to the same messages reveal the opposite patterns, underscoring the importance of pilot-testing behavioral nudges in the real world before scaling them up. In the second RCT, we further find that receiving a second reminder boosts appointment and vaccination rates by 52% and 16%, respectively. Our findings suggest that text-based nudges can substantially increase and accelerate COVID-19 vaccinations at almost zero marginal cost, highlighting the promising role of behavioral science in addressing a critical component of the COVID-19 pandemic response.

Emphasize personal health benefits to boost COVID-19 vaccination rates

“…First, we considered one-shot information treatments, which may understate the potential impact from an ongoing information campaign. Second, while we purposefully focused on messages that appeal to different motivations, messages that appeal to psychological effects (e.g., the endowment effect) also have been found to increase COVID-19 vaccinations (11). Third, we examined intentions to get vaccinated, rather than actual behavior, because the timing of the survey preceded widespread availability of COVID-19 vaccines.…”

“…The COVID-19 vaccine presents a novel context to study hesitancy because of the speed of the vaccine development and political polarization related to the pandemic and the vaccine. We focused on messages that appeal to motivations to take or abstain from taking vaccines (e.g., rather than to psychological effects) (11), and identified messages with particularly high potential to increase COVID-19 vaccinations, based on literature that examines messages aimed to boost childhood vaccines (12) and other COVID-19 preventive behavior (13), as well as worries that deter COVID-19 preventive behavior (14,15).…”

The Vaccination Process against the COVID-19: Opportunities, Problems and mHealth Support

“…The escape also depends on how the institutions reach the citizens through mTech. Subtleties in the composition of messages and the language used to reach them are therefore also important to affect their behaviour [48]. In [48], the authors presented two sequential randomized controlled trials (RCTs) that tackle this challenge with behavioural science insights.…”

“…Subtleties in the composition of messages and the language used to reach them are therefore also important to affect their behaviour [48]. In [48], the authors presented two sequential randomized controlled trials (RCTs) that tackle this challenge with behavioural science insights. In the first RCT, text messages designed to make vaccination salient and easy to schedule boost appointment and vaccination rates by 86% and 26%, respectively.…”

“…In our study, it has been highlighted how mobile technology can be particularly helpful in this moment on this issue. It was highlighted how specific Apps can play an important role as a communication tool capable of allowing the dissemination of correct information, fighting the infodemic [44,45,47], and recalling citizens with calibrated messages [48].…”