Research Methods in Epidemiology.

Epidemiology is the study of the distribution and determinants of health-related states and in specified populations and the application to control health problems. Classified as either descriptive or analytical, a variety of epidemiologic approaches can be used to allow assessment of hypothesized risk factor exposure with disease outcomes. This article reviews salient aspects of epidemiologic research methods that are used repeatedly in articles in this volume on public health, neuroepidemiology, and health systems.