Error in Epidemiologic Research
9.1 Introduction Random error and systematic error Effective use of epidemiologic information requires more than knowing the facts. It requires understanding the reasoning behind the methods. A good place to…
Epidemiology Past and Present
1.1 Epidemiology and its uses What is epidemiology? The word epidemiology is based on the Greek roots epi (upon), demos (the people, as in “democracy” and “demography”), and logia (“speaking…
Experimental Studies
6.1 Introduction Epidemiologic experiments are also called trials. The word trial comes from the Anglo-French root trier, meaning “to try” or “to put something to a test.” Epidemiologic trials put…
Outbreak Investigation
12.1 Background Initial detection of outbreaks An outbreak is an epidemic or upsurge of cases in a defined geographic region or easily defined subpopulation. Outbreaks come to the attention of…
Statistical Interaction: Effect Measure Modification
15.1 Two types of interaction Types of interaction Epidemiologists speak of two distinct types of interaction: biological interaction and statistical interaction. Although these concepts share the term “interaction,” these are…
Descriptive Epidemiology
4.1 Introduction What is descriptive epidemiology? Descriptive epidemiology is a general term used to refer to a broad array of epidemiologic activities whose primary purpose is to describe disease occurrence…
Causal Concepts
2.1 Natural history of disease Stages of disease The natural history of disease refers to the progression of a disease in an individual over time. This includes all relevant phenomena…
Introduction to Epidemiologic Study Design
5.1 Etiologic research Hypotheses are nets: only he who casts will catch. Novalis Hypothesis statement The goal of analytic epidemiology is to clarify causal relations between various determinants (“exposures”) and…
The Infectious Disease Process
11.1 The infectious disease process Studying infectious disease epidemiology is important for two different reasons. First, infectious disease epidemiology provided the original model for the study of disease on a…
Case Definitions and Disease Classification
16.1 Case definitions Establishing a case definition In this chapter, we consider criteria for defining cases and the standardized system of disease nomenclature known as the International Classification of Disease…
