Perceived ideological polarization, trust in science and healthcare, and COVID-19 vaccination intention: A four-wave cross-lagged mediation panel analysis

Ideological polarization is often theorized to erode trust in science and healthcare, thereby reducing compliance with health guidelines and vaccine uptake. In this study, we examined the longitudinal relationships between perceived ideological polarization, trust in science and healthcare, and COVID-19 vaccination intention, using a four-wave panel design. We analysed four waves of panel data from a sample of 488 Slovenians, representative by gender, age, and education. Pearson correlations and a random intercept cross-lagged panel model (RI-CLPM) were used to assess both within- and between-person associations, and to test whether trust in science and healthcare mediated the relationship between perceived ideological polarization and vaccination intention over time. Baseline correlations showed a positive association between perceived ideological polarization, trust, and vaccination intention, though these associations weakened and became non-significant in later waves. RI-CLPM results revealed no evidence of causal, within-person effects of perceived ideological polarization on later trust or vaccination intention, and no longitudinal mediation pathways. However, between-person effects indicated that individuals with consistently higher trust in science and healthcare reported higher vaccination intentions across time. These findings challenge the assumption that ideological polarization undermines trust and vaccination intention, suggesting that cross-sectional associations observed in prior research may reflect stable between-person differences rather than dynamic causal processes. By distinguishing cross-sectional from longitudinal evidence, this study underscores institutional trust as the key predictor of vaccination intention and calls for comparative research across political and cultural contexts.