On decomposing the causes of health sector inequalities with an application to malnutrition inequalities in Vietnam

The authors propose a method for decomposing inequalities in the health sector into their causes, by coupling the concentration index with a regression framework. They also show how changes in inequality over time, and differences across countries, can be decomposed into the following: Changes due to changing inequalities in the determinants of the variable of interest. Changes in the means of the determinants. Changes in the effects of the determinants o the variable of interest. The authors illustrate the method using data on child malnutrition in Vietnam. They find that inequalities in height-for-age in 1993 and 1998 are accounted for largely by inequalities in household consumption and by unobserved influences at the commune level. And they find that an increase in such inequalities is accounted for largely by changes in these two influences. In the case of household consumption, rising inequalities play a part, but more important have been the inequality-increasing effects of rising average consumption and the increased protective effect of consumption on nutritional status. In the case of unobserved commune-level influences, rising inequality and general improvements seem to have been roughly equally important in accounting for rising inequality in malnutrition.