Commentary: comprehensive approaches are needed for full understanding

摘要

Braveman et al criticise the World Health Organiztion's approach of measuring the full spectrum of health inequalities in a population. They argue for a selective approach in which only health inequalities correlated with factors such as income, social class, or race should matter. Such a selective approach runs counter to the literature on inequality in other disciplines and runs the risk of discouraging scientific inquiry into the causes of inequality. I will use an example to illustrate the differences between the selective and comprehensive approaches to health inequality. Gakidou and King have estimated the risk of death for each child in 50 countries using household survey data. These risks of death are based on a model that includes a range of sociodemographic variables such as wealth, education, and urban location. In addition, they include an estimate of systematic variation in risk of child mortality not captured by the sociodemographic variables. This can best be thought of as non-random variation in risk due to unmeasured variables. The figure shows the results of their analysis for the Central African Republic. The median risk of death for children is lower in wealthier households. But within each wealth quintile, risk of death varies widely. This variation is systematic or non-random variation in risk of death; it is not simply showing the effects of chance on outcomes.