Updated meta-analysis of environmental Kuznets curve: Where do we stand?

The relationship between income growth and environmental quality has been frequently investigated in the literature. These investigations are not unified on a single point and have yielded in a broad spectrum of conflicting results. Major portion of the literature argues that there exists an inverted U-shaped relationship between per capita income and environmental quality. While another stream of research opposes these findings and rejects environmental Kuznets curve (EKC). To investigate these variations, the present study synthesizes the existing findings and conducting meta regression analysis on a broad level. The contribution of this study is twofold; first, a framework, Preferred Reporting Items for Meta Regression Analysis (PRIMRA), has been developed, which is aimed to provide a pathway for future meta-analyses. This study itself has been carried out in the light of this framework. Second, this is the very first attempt to synthesize EKC literature by using quantitative methods on a broad level. Reviewing 101 research papers published during 2006–2019, we have found a strong evidence in support of EKC. It has been found that this relationship is a long run phenomenon and irrelevant to the choice of econometric tools employed or type of data used. Although the results show variations with the choice of environmental degradation indicators.