effect of wealth on the health expenditure: application of the development approaches adopted by the opec countries

Background: investment in health is considered as an essential requirement in human life. we aim to investigate the relationship between the healthcare expenditure and the wealth for the opec countries.method: the panel data of 12 countries between 2007 and 2018 were analyzed by the generalized method of moments (gmm) and the bayesian panel data analysis, applying the healthcare expenditure, gdp per capita, oil price, population growth rate, inflation, life expectancy, and mortality rate as variables.results: the results show that the expenditure of healthcare is significantly and negatively linked to the economic growth and the oil price. in addition, the population growth rate, inflation, life expectancy, and the mortality rate have positive effects on the healthcare expenditure. the comparison of the results of these methods supports the convergence and the close relationship between the model parameters; therefore, the model performs well on the available data. the human capital is an essential determinant in the economic situation of the opec countries and their growth improvement. the economic planners and policy makers have to consider more health-based investments in the human capital quality to better improve the people's standard of living.conclusion: this study helps to develop policies on the health quality and the expansion of biotechnology, pharmaceuticals, and information technology.