Interventions to Reduce Vaccine Hesitancy Among Adolescents: A Randomized Controlled Trial.

Vaccines currently prevent several million deaths every year and more lives could be saved if vaccination take up increased. The World Health Organization identifies vaccine hesitancy as one of the ten most important threats to global health and emphasizes the importance of devising interventions to reduce vaccine hesitancy. The two most promising interventions rely on consensus messaging, which has robust but small effects, and interactive discussion, which has larger effects, but is difficult to scale up. School-based interventions aimed at adolescents have the potential to make the best of both types of interventions. Interventions that take place in schools can be conducted over longer periods of time (up to several hours) and are rolled out by a figure that is typically trusted and respected (the teacher). Moreover, intervening during adolescence is particularly timely since important vaccines are delivered at that age (most notably the human papillomavirus vaccine), and because attitudes towards vaccination during adolescence might have a long-lasting impact, as is the case for other health related attitudes.

This study tests the effectiveness of two interventions, a pedagogical intervention based on consensus messaging, and a chatbot intervention designed to mimic interactive discussion, on 9th grade French pupils.