Other factors tested but trust stood out statistically.
There are other factors besides trust that might influence vaccination rates, including accessibility and vulnerability. We analyzed the old-age dependency ratio and health care expenditure per inhabitant but did not find statistically significant dependencies. This suggests that while these factors could theoretically matter, in our analysis trust emerged as the key differentiator when controlling for these other variables across EU member states.
— Get Vaccinated? How Trust In Institutions Determines COVID Vaccination Rates In The EU · Forbes