• Chile had world’s highest COVID-19 vaccination rate • A Discrete Choice Experiment (DCE) was conducted to understand vaccine programme preferences • Results reveal the most preferred vaccine program characteristics • Analysis identified 81% preferred vaccine programmes, and 19% preferred to opt out Chile achieved the world’s highest COVID-19 vaccination rate by March 2021, reflecting a strong vaccination culture. Nevertheless, coverage rates alone do not fully capture public preferences for vaccine characteristics and social restrictions policies. This study aims to quantify how Chileans trade off specific vaccine characteristics and social restriction policies when choosing vaccination programmes, and to identify distinct preference patterns within a high vaccination coverage context. A discrete choice experiment (DCE) was administered to 3,004 respondents in Chile as part of the VaxPref database. Respondents completed choice tasks selecting between two hypothetical vaccination programmes, which varied in terms of vaccine characteristics and social restrictions policies, or an opt-out option. The experimental design included seven attributes: vaccine effectiveness, risk of severe side effects, duration of protection, time between the first clinical trial and market approval, manufacturer origin, stringency of social restrictions, and a vaccine mandate to return to work. Data were analysed using a multinomial logit (MNL) and a latent class (LC) model. MNL results showed respondents preferred greater effectiveness, lower severe risk of side effects, longer protection, longer trial-to-approval times, vaccines from Western countries (EU, UK, USA), reduced social restriction stringency and increased strength of the vaccine mandate to return to work. LC analysis identified two preference classes: (Class 1) a majority (81%) with preference for one of the vaccination programmes, and (Class 2) a minority (19%) with preference for the opt-out alternative. Lower probability of Class 1 membership was associated with higher health risk aversion, being female, and having higher cognitive skills. Class 2 was more sensitive to the severe risk of side effects, trial-to-approval time, and showed no statistically significant response to the vaccine mandate to return to work. The Chilean case highlights within-country heterogeneity in preferences for vaccination programmes, even in a high-coverage setting. These findings provide context-specific insights that may inform more tailored vaccination policies and communication strategies.
Bruzzo-Gallardo et al. (Sun,) studied this question.