Social preferences for adopting new vaccines in the national immunization program: A discrete choice experiment

Governments regularly have to decide whether new vaccines should be adopted in their national immunization program. These choices imply complex trade-offs of epidemiological, medical and socio-economic criteria. We investigated how the population in Flanders (Belgium) wants their government to set vaccine-funding priorities. In December 2019, we executed a discrete choice experiment in a sample of the Flemish population (N = 1636). In total, we analysed 16 360 choices between vaccines competing for funding, described in terms of eight characteristics. Using a panel mixed logit model, we quantified the relative importance of each characteristic and investigated differences in preferences across respondent groups. The observed vaccine priorities were different from those that would be identified through cost-effectiveness analysis. People valued the health impact from infectious diseases differently than their weight expressed in QALYs would suggest. Mortality and frequently occurring mild illness were valued higher, whereas lasting morbidity received lower weight. Contribution of the vaccine to disease eradication and uncertainty in vaccine effectiveness were both highly influential factors. Health equity impact was also important whereas the economic impact of the disease did not matter at all. Our results can be used to incorporate public values into vaccine decision-making.