Understanding inequalities in COVID-19 vaccination between migrants and non-migrants in Germany: The role of psychological factors of vaccine behaviour

Background: Understanding the underlying mechanisms for differences in vaccine uptake between migrants and non-migrants is crucial in order to design targeted interventions encouraging vaccination and to ensure vaccine-related equity. Therefore, this study examined to what extent migration-related disparities in COVID-19 vaccination were associated with psychological factors, based on the established 5C model of vaccine behaviour (Confidence, Complacency, Constraints, Calculation, Collective Responsibility). Methods: Data were obtained from the German study "Corona Monitoring Nationwide - Wave 2" (RKI-SOEP-2 study), which was carried out between November 2021 and March 2022. The association between COVID-19 vaccination and migration status, while considering the psychological factors, was investigated using multivariable binary logistic regressions. A decomposition analysis (Karlson-Holm-Breen method) was conducted to examine the extent to which migration-related disparities in vaccine uptake were associated with the psychological factors of the 5C framework. Results: Migrants were less likely to be vaccinated against COVID-19 compared to non-migrants, especially participants from the Middle East and North Africa (MENA) region. Our decomposition showed that almost two-thirds of the disparities in COVID-19 vaccine uptake between migrants and non-migrants were associated with the psychological factors (first-generation: 61.2%, second-generation: 64.2%). Confidence in safety of the vaccine was the most relevant factor in the 5C framework. Furthermore, the results highlighted the importance of a differentiated analysis regarding country of origin: While the 5C model accounted for only 19.4% of the difference between participants from the MENA region and non-migrants, the proportion for participants from Eastern Europe was 73.5%, suggesting that the underlying mechanisms for the lower uptake in the MENA group need further investigation. Conclusions: Overall, migration-related disparities in COVID-19 vaccination were significantly associated with differences in psychological factors of vaccine behaviour. To increase vaccine acceptance within the heterogeneous group of migrants in general, tailored and proactive health communication interventions are needed.