Topic overview

Start with the big picture

Descriptive epidemiology organizes health information by characteristics such as place. Geographic comparisons can show that health events are not distributed uniformly across locations, while urban–rural comparisons offer a broad way to examine differences between settings. These descriptions help identify patterns and define questions for further investigation; by themselves, they do not establish why a pattern exists. This introduction focuses on place as a descriptive lens and on distinguishing geographic variation from urban–rural contrasts. The full lesson develops these ideas further, while this preview provides a starting point for considering how location can structure epidemiologic observation.