Searching for information on health disparities and equity can be tricky because of how quickly language changes. Databases and authors can be slow to make the transition to current terminology. Historical resources probably will use outdated (and possibly offensive) terminology. Keep this in mind when searching.
Depending on the search tool that you are using (catalog, database, web search), you may need to search for multiple terms. Here are some terms to consider for both textword and subject searching (remember that some databases have specific subject terms to use).
Combine the above terms with terms like these:
or with terms that are disease/condition-specific (like asthma, heart disease, etc.)
Rural health disparities: Public health, policy, and planning approaches by 
Application of the political economy to rural health disparities by 
Urban Health by 
