Relative index of inequality

The interpretation of RII is similar to the relative risk. It summarizes the relative risk for the most advantaged group (at the top of the hierarchy) compared to the least advantaged group (at the bottom of the hierarchy). This interpretation assumes that the variables have been scored so that higher scores are consistent with increased risk. For example, an RII of 1.88 (95% confidence intervals 1.27 to 2.77), an indicator of low SES, on the risk of long term illness, implies that those in the most deprived group are 1.88 times more likely to experience illness than those in the least deprived group. == Limitations of RII ==

One disadvantage of the RII is that it may capitalize on skewed data, inflating the apparent relative risk. A second limitation is that a large RII may arise for two reasons. First, it may represent a large effect of SES on disease. Second, it may reflect large differences between those with the most SES and those with the least (i.e. large inequalities in SES itself). == References ==