Vol. 28 No. 1 (2025)
Articles

ON THE EFFECTIVENESS OF COVID-19 VACCINES IN REDUCING MORTALITY RATES WITHIN THE EU AND ITS RELATIONSHIP WITH HUMAN DEVELOPMENT

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  • Svetoslav Bliznashki
DOI: https://doi.org/10.7546/PsyRB.2025.28.01.06

Published 07/21/2025

Keywords

  • COVID-19,
  • vaccination,
  • mortality,
  • linear mixed model,
  • individual growth curves

How to Cite

Bliznashki, S. (2025). ON THE EFFECTIVENESS OF COVID-19 VACCINES IN REDUCING MORTALITY RATES WITHIN THE EU AND ITS RELATIONSHIP WITH HUMAN DEVELOPMENT. Psychological Research (in the Balkans), 28(1). https://doi.org/10.7546/PsyRB.2025.28.01.06

Copyright (c) 2025 Psychological Research (in the Balkans)

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

Abstract

Purpose: We try to estimate and quantify the effect of vaccination rates on the overall COVID-19 death toll on a monthly basis. We limit our analyses to the duration of the year 2021 and within 25 countries which are current or former (UK) members of the EU since these countries follow similar approaches to testing and reporting different COVID-19 related statistics.
Methods: We explored the effect in question by comparing the cumulative number of people vaccinated up to the end of each month and the total number of deaths occurring during the next month while controlling for several measures including number of new COVID-19 cases, diabetes prevalence, cardio vascular death rates and Human Development among others.
Results: A Linear Mixed Model, a Multilevel Poisson Regression, and an Individual Growth Curves Analysis were employed, all of which suggested the same conclusions and comparable estimates indicating that one percentage point monthly increase in the total number of vaccinated people was associated, on average, with a decrease of more than four deaths due to COVID-19 per general population of 1 million for the next month with the effect being highly significant. Human Development Index seems to moderate the relationship between infection and mortality rates.
Conclusions: Our results are consistent with a substantial effect of vaccination rates on reducing the overall death toll of COVID-19 throughout the EU. We illustrate the potential cumulative vaccination effect by a case study involving the most and least vaccinated EU countries. The possibility of an indirect effect of vaccination rates on mortality rates through infection rates is also discussed.

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