Ownership Language in Text Reminders Yields Action

Researchers show the benefit of text reminders to schedule and receive a COVID-19 vaccine booster

We all strive to be healthy but juggling diet, exercise and doctors’ visits with work, family and other obligations can be daunting. Vaccinations contribute to a healthy lifestyle, but this task often falls off the radar. This fact was abundantly clear as the U.S. government rolled out COVID-19 vaccination and booster campaigns. 

Silvia Saccardo, associate professor in the Department of Social and Decision Science at Carnegie Mellon University, and Hengchen Dai, associate professor at UCLA Anderson school of Management conducted a series of field experiments in collaboration with colleagues at UCLA Health over the past three years to study effective campaigns grounded in behavioral science to prompt people to sign up and show up for their various COVID-19 vaccination appointments.

Effective strategies for vaccine appointment uptake

In 2021, Dai, Saccardo and her colleagues published an article in the journal Nature, which found that text nudges leveraging psychological ownership were the most effective method to get people to schedule and show up for the COVID-19 vaccine appointment. Saccardo’s team built on these findings to field test a new series of interventions for the newest COVID-19 boosters. The latest results are available in the March 14 issue of the journal “Nature Human Behaviour.”

“When COVID hit, we tested intervention to promote uptake of the initial dose of the COVID-19 vaccine” said Saccardo, a contributing author on the paper. “In this new study, we partnered with the same healthcare provider to evaluate the COVID booster campaign. This was a great opportunity for testing how interventions that worked early on during [the pandemic] work under new circumstances. We also studied whether interventions deemed effective by research studies capturing vaccination intentions, and interventions predicted to be effective by experts actually  transfer to the field” 

The researchers designed three field experiments to evaluate different interventions for promoting vaccination validated by either prior field research, hypothetical studies or supported by expert intuition. They tested how these intervention affect the uptake of the COVID-19 bivalent boosters in a population who had previously completed the primary COVID-19 vaccine series. The study was conducted in collaboration with UCLA Health, a large healthcare system in California, which participated in previous evaluations.

“We focus on these approaches because they reflect common ways researchers and practitioners decide how to [use] behavioral science to address particular challenges,” said Hengchen Dai, associate professor at the UCLA Anderson School of Management and contributing author on the paper. “It is important to test the knowledge from lab experiments in the field because what works in the lab may not change consequential behaviors in a complex real-world setting.”

Insights from field experiments

The megastudy design allowed Saccardo, Dai and their colleagues to investigate interventions that build on field work that emerged during the early stages of COVID-19 vaccine rollout. The study consisted of randomized controlled trials that evaluated the interventions delivered through text-based reminders to 314,824 participants.

The study evaluated the effect of various reminders on booster uptake, including 1) reminders with language encouraging participants to ‘claim your dose;’, a approach found effective in their 2021 paper in Nature 2) the impact of a doctor’s endorsement of a vaccine, which had been found effective by other work, 3) messages crafted to correct misperceptions about the booster, and 4) messages encouraging patients to bundle the covid-19 booster with the flu shot, an approach used by many pharmacies and even encouraged by the CDC.

“Our main finding is that interventions that worked in the past in field studies—reminders, psychological ownership language and doctor recommendations — worked again,” said Saccardo. “The interventions that show promising effect with online studies or that were expected to work by experts did not work in the field.”

The team concludes that strong partnerships with fellow researchers, practitioners and funders along with the field-tested interventions can be effective in breaking through the wall of inaction and tackle challenges such as that of encouraging COVID vaccination and beyond.

Saccardo and Dai were joined by Maria A Han, Juyea Hoo, Jeffrey Fujimoto and Sitaram Vangala at UCLA David Geffen School of Medicine on the paper, titled “Field-Testing the Transferability of Behavioural Science Knowledge on Promoting Vaccinations.” The project received funding from the National Institutes of Health, UCLA Health, Anderson School of Management and Carnegie Mellon University.