Multidimensional Determinants of Life Expectancy in Developing Countries: Evidence From Preston Curve Hypothesis

ABSTRACT The determinant of quality health outcomes is multidimensional, with GDP per head as one aspect. Due to the significance of quality health outcomes like life expectancy in developing countries, exploring health outcome determinants becomes crucial. In this study, we explore the Preston curve hypothesis by analysing GDP per capita and life expectancy interdependence in 102 developing countries between 1991 and 2023. We also consider exogenous factors such as public health spending and environmental pollution influencing the GDP per capita–life expectancy nexus. Disaggregating the panel data into a full panel, low, middle, and high‐income developing economies, we apply the two‐step Sys‐GMM, pooled‐FMOLS, and Dumitrescu–Hurlin (DH) causality techniques for data analysis. The result reveals that GDP per capita enhances life expectancy across all income levels in developing economies. However, for low‐income developing economies, public spending negatively impacts life expectancy but positively affects middle‐ and high‐income developing economies. For all categories of panels, environmental pollution proxied with CO 2 reduces life expectancy. Our study concludes by offering a practical policy for developing economies to drive investment in health‐related human development crucial for quality‐of‐life improvement.