Developing a practical tool for measuring parental vaccine hesitancy: A people-centered validation approach in Dutch

Vaccine hesitancy (VH) about routine childhood vaccinations drives falling vaccine uptake rates. This is a major public health challenge and therefore important to monitor uniformly. The challenge is that different methods are used to measure VH and that, in non-English language, there may not be an unequivocal translation of VH terminology. We aimed to develop and validate a method to assess VH in a simple and self-reported manner, with a mixed-methods study using a people-centered approach with a diverse group of parents and illustrated in Dutch. In the quantitative part, parents were asked to rate experienced vaccine hesitancy on a 10-point Likert scale, using five differently worded Dutch translations for VH. We analyzed internal consistency with Cronbach’s alpha and correlation with the short parental attitudes about childhood vaccination (PACV-5) scale. A total of 532 parents participated in the survey. We found that the five worded alternatives measured the same construct, indicated by a Cronbach’s alpha of 0.95. The wording resembling ‘doubt’ showed highest correlation with the PACV-5 score (coefficient −0.525, <i>p</i> &lt; .001). In the qualitative part of this study, we conducted cognitive interviews with 12 lower educated parents to evaluate the comprehensibility and interpretation of the question and VH translations. The findings reinforced and added to the quantitative findings that ‘doubt’ is the preferred wording. Based on the integrated results, we developed the Vaccine Hesitancy Assessment (VHA) tool. We encourage its use for monitoring purposes at the time of decision-making as this may provide a window of opportunity for decision-support interventions. Children less often receive vaccinations due to vaccine hesitancy. This is a major health problem that we want to monitor. But, there are different ways to measure hesitancy and to translate hesitancy into other languages. This makes monitoring and comparison between countries difficult. In this study, we developed a simple measure for hesitancy in a self-reported manner. Input from parents played an important role. We used two methods to collect information: numeric information from questionnaires and views and preferences of parents from interviews. In this study, we looked at five possible translations for hesitancy in Dutch. In the questionnaires, parents were asked to score their level of hesitancy from 1 to 10 for each of the five translations. We then compared the scores for each different translation with each other and with another often used measure of vaccine hesitancy. A total of 532 parents completed the questionnaire. We found very similar scores for the hesitancy questions with different translations. But, the translation resembling ‘doubt’ in Dutch corresponded most with the often used measure for vaccine hesitancy. Additionally, we interviewed 12 parents about how they understood the sets of question and answer to score their level of hesitancy. We evaluated how easy this was to read and which translation matched best with their understanding. These findings were in line with the results from the questionnaire and gave directions for improvement. This resulted in a measure called the Vaccine Hesitancy Assessment (VHA) tool. This tool can be used to monitor vaccine hesitancy.