Imagine an individual who is afraid of needles, has no trust in the medical authorities, believes the world is flat, and believes that vaccines are not safe or effective. Despite having characteristics that are commonly associated with a negative attitude towards vaccination, this person got vaccinated against COVID-19. You might wonder, why did this person got vaccinated? This question is at the core of my PhD project which resolves around the topic of understanding vaccine hesitancy in the Netherlands. Why do some people get vaccinated despite having characteristics that would suggest otherwise and why do some people not get vaccinated despite having personal characteristics that would suggest that they would be vaccinated? And importantly, what might we learn from these people that public health officials can apply to others to lower vaccine hesitancy? We try to answer these questions with a positive deviant approach.
The positive deviant approach, which originated from nutrition research, consists of three phases. The first phase entails the identification of the positive and negative deviants. To identify the positive and negative deviants, we asked a large representative sample in the Netherlands intentions to get vaccinated against 16 diseases (e.g., measles, COVID-19, flu), 5 vaccination behavioral questions (e.g., participation National Immunization Program, travel vaccines, COVID-19), and statements on a wide range of predictors (e.g., religiosity, fear of needles, trust in authorities). By comparing their actual scores on the behavioral and intention questions with the predicted scores based on their scores on the wide range of predictors, we have determined the positive and negative deviants.
The second stage entails the qualitative in-depth study of the positive and negative deviants. The goal of this stage was to identify the reasons for positive deviants to get vaccinated and to identify the barriers for negative deviants to not get vaccinated. We interviewed approximately 20 individuals with deviant COVID-19 vaccination attitudes in which we asked them questions about how they formed their attitude, whether their attitude changed throughout the pandemic, and what could change their attitude in the future. One of the results we found was that being able to go abroad on a holiday was an important reason for positive deviants to get vaccinated.
In the third and final stage, we are now developing interventions based on the reasons to (potentially) remove the barriers for people to not get vaccinated. What worked for some positive deviants to overcome the barrier of getting vaccinated, might also work for other people. By testing these on a representative sample, we might inform public health officials with interventions that can help to take the final steps to reach herd immunity for childhood vaccination uptake.
If you want to learn more about my PhD project, the steps we are currently taking in developing interventions, some results we already have, or have interesting insights from your work, I am happy to share an (online) coffee with you to talk about it. You can contact me at m.a.m.matthijssen@tilburguniversity.edu