Some UCSF projects address cross-cutting health topics that are global in scope, yet not specific to a particular country. Often these topics involve macro-economic forces, such as globalization. For instance, the global HIV epidemic has impacted the largest number of people in sub-Saharan Africa, yet has also impacted and elicited a response from countries around the world. Often health economics and policy research addresses particular vulnerable groups or draws conclusions about sub-groups of countries grouped by economic indicators. UCSF educational programs seek to provide training opportunities and short-term research projects for health sciences students and master's students in countries around the world.