Introduction to Epidemiology
Epidemiology is considered the basic science of public health, and with good reason. Epidemiology is: • • • A quantitative basic science built on a working knowledge of probability, statistics, and sound research methodology A method of causal reasoning based on developing and testing hypotheses pertaining to occurrence and prevention of morbidity and mortality A tool for public health action to promote and protect the public’s health based on science, causal reasoning, and a dose of practical common sense (2).
As a public health discipline, epidemiology is instilled with the spirit that epidemiologic information should be used to promote and protect the public’s health. Hence, epidemiology involves both science and public health practice. The term applied epidemiology is sometimes used to describe the application or practice of epidemiology to address public health issues. Examples of applied epidemiology include the following: • • • • the monitoring of reports of communicable diseases in the community the study of whether a particular dietary component influences your risk of developing cancer evaluation of the effectiveness and impact of a cholesterol awareness program analysis of historical trends and current data to project future public health resource needs
Objectives
After studying this document and answering the questions in the exercises, you should be able to do the following: • • • • • • • • • • • Define epidemiology Summarize the historical evolution of epidemiology Describe the elements of a case definition and state the effect of changing the value of any of the elements List the key features and uses of descriptive epidemiology List the key features and uses of analytic epidemiology List the three components of the epidemiologic triad List and describe Hill’s criteria of causation Understand the natural history of disease and the three types of prevention Understand infectivity, pathogenicity, and