Longitudinal ecological analysis of the relationship between childhood vaccination levels and population mortality and life expectancy in Türkiye

This longitudinal ecological study aimed to analyze the relationship between childhood vaccination levels and social mortality levels and life expectancy in Türkiye. The study used data on life expectancy, mortality rates, and vaccination rates for the period 1980-2023 from the Country Reports dataset compiled by the World Health Organization and published by the World Bank. The study is modeled on descriptive and correlational survey methods. The relationship and impact of vaccination rates on mortality and life expectancy over time were analyzed. Measles immunization rate (r = 0.908; p < 0.01), hepatitis B vaccinations (HepB3) immunization rate (r = 0.875; p < 0.01) and diphtheria, pertussis, and tetanus vaccine (DPT) immunization rate (r = 0.873; p < 0.01) were significantly and positively correlated with life expectancy. Measles immunization rate (r = -0.571; p < 0.01), HepB3 immunization rate (r = -0.809; p < 0.01) and DPT immunization rate (r = -0.651; p < 0.01) were significantly and negatively correlated with mortality. Effect of HepB3 on life expectancy was statistically significant and positive (B = 0.229; p < 0.01). Explanatory power of the model was 78.9% of total variance. According to regression analysis, effects of measles and DPT on life expectancy were insignificant (p > 0.05). Regression effects of HepB3 on mortality was statistically significant and negative (B = -0.260; p < 0.01). Explanatory power of the model was 69.8% of total variance. Regression effects of measles and DPT on mortality were insignificant (p > 0.05). As a result of vaccinations over time, mortality rates, particularly from hepatitis B, have decreased, and average life expectancy has increased significantly. Therefore, vaccination is an important, effective, and efficient health tool for society.