Health gradients in South Africa: Inequalities in the measure of the beholder

As the literature on health inequalities continues to grow very few studies have tested the sensibility of this measure to the choice of welfare indicator. In this paper we use data from an aging survey in South Africa to evaluate the health gradients using two measures of economic status: consumption per capita and an asset index. In particular, we measure the concentration indexes for a variety of health indicators ranging from general health service utilization to individual self-reported and biomarker outcomes. We find that the concentration indexes for different health indicators differ across economic indicators suggesting that the choice of welfare indicator can lead to different estimations of inequalities. In line with other studies, these results advocate for greater caution when selecting the economic indicator in the analysis of inequalities and for more explicit testing of different indicators in future studies. Overall, the results call for a greater understanding of how SES can influence health to generate appropriate measurements of health inequalities.