Defining health inequality: why Rawls succeeds where social welfare theory fails.

While there has been an important increase in methodological and empirical studies on health inequality, not much has been written on the theoretical foundation of health inequality measurement. We discuss several reasons why the classic welfare approach, which is the foundation of income inequality analysis, fails to provide a satisfactory foundation for health inequality analysis. We propose an alternative approach which is more closely linked to the WHO concept of equity in health and is also consistent with the ethical principles espoused by Rawls [A Theory of Justice. Harvard University Press, Cambridge, MA, 1971]. This approach in its simplest form, is shown to be closely related to the concentration curve when health and income are positively related. Thus, the criteria presented in our paper provide an important theoretical foundation for empirical analysis using the concentration curve. We explore the properties of these approaches by developing policy scenarios and examining how various ethical criteria affect government strategies for targeting health interventions.