EPI Challenge For You

What Is Epidemiology?

Epidemiology is the scientific method used to investigate and analyze health and disease in populations. The ultimate purpose is to use this knowledge to prevent and control health problems for the good of the public. To do this, epidemiologists are disease detectives. They track the patterns and trends of health, health behaviors and disease in populations (asking Who, Where, and When). They use clues to try to figure out what factors influence or cause these patterns and trends (asking Why). Epidemiologists are interested in a wide range of health-related topics. For example, they may study lifestyle behaviors such as diet or drug use, infections like HIV/AIDS or influenza, chronic conditions such as heart disease or obesity, physical injury, or psychological stress.

The scope of epidemiology is described in the diagram below. It shows six steps and the kinds of questions that are asked at each step. As the flow of the diagram illustrates, what is learned from epidemiology studies can often be used to model public health prevention and control programs; this is one reason why epidemiology is often said to be the science of public health.