I have a guest post on the subject over at the very fine Inequalities blog. Here's the opening paragraph:
The terms we use to describe inequality are important. They’re important because there are different perspectives about (1) what terms should be used for (2) which referents (3) in which circumstances, and these reveal what is actually at stake. Thus, whether the term “disparities” is used in lieu of “inequalities” or “inequities” actually matters a great deal, at least in part because there is an inescapable ethical valence to the term “inequities” that is absent from the more neutral term “disparities.” The question is whether the ethical valence is something that ought to be included in public health policy discourse, or whether, given the difficulty in measuring it, it should be avoided where possible.