Chapter 6: Interpreting the Tables and Graphs
suffers from impairment in activities of daily living with respect to hearing, seeing, and walking. The concentration curve for hearing impairment lies above the 45° line, which confirms that this health condition is more prevalent among the poor. By contrast, the concentration curve for seeing impairment lies below the 45° line, which means that this health condition is more concentrated among the rich. The concentration curve for walking limitations is very close to the 45° line, which indicates very little association between this health condition and income.
Explaining Inequalities in Health Concepts Tables H6 and H7 show two alternatives for the decomposition of the health concentration index by health determinant. In these tables, it is possible to distinguish inequality (the extent to which health is linked to income) from inequity (the part of inequality deemed unjustified) by separating the factors into two different groups. On the one hand, the standardizing variables are the variables whose correlation with health is deemed justifiable. Demographic factors such as age and gender are common examples of such variables. On the other hand, control variables are the factors whose correlation with health is deemed unfair. These variables “control” health standardization in the sense that they prevent standardizing variables from picking up the effect of variables with which they are correlated. Moreover,
Table H6: Decomposition of the Concentration Index for Health Outcomes, Linear Model adlhearing
adleyesight
adlwalk
0.0002 0.1036 0.1038
0.0002 0.0802 0.0801
0.0009 0.0971 0.0962
Control variables pcexp Subtotal
0.1015 0.1015
0.0256 0.0256
0.0405 0.0405
Residual Inequality (total) Inequity / Unjustified inequality
0.0606 0.0583 0.1621
0.0040 0.1096 0.0295
0.0411 0.0147 0.0816
Standardizing (demographic) variables male age Subtotal
Source: Authors.
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