Encouraging COVID-19 vaccination via an evolutionary theoretical approach: A randomized controlled study in Japan

We aimed to examine the effect of a message that target the fundamental human motive of kin care on COVID-19 vaccination recommendations among participants with young children, based on an evolutionary theoretical approach.

Participants with young children (n = 969) were randomly assigned either to a group that received an intervention message that targeted the fundamental motive of kin care, or that targeted the fundamental motive of disease avoidance, or a control message. Intention to receive COVID-19 vaccination was assessed both before and after reading the messages. A one-way ANOVA with Tukey's or Games-Howell test was conducted.

An intervention message targeting the fundamental motive of kin care and disease avoidance significantly increased intention of vaccination versus a control message (p < 0.001, respectively).

The evolutionary theoretical approach that focuses on fundamental human motives has the potential to extend the communication strategy for COVID-19 vaccination recommendations.

Health professionals should deliver messages that target the fundamental motive of kin care as well as messages about the susceptibility and severity of COVID-19 and vaccine efficacy (e.g., "Get vaccinated against COVID-19 for your child's sake, because if you are infected, you will be unable to care for your child.").