Lecture 1: Epidemiology - Definitions and History

Public Health

Organized community effort to protect and improve health through prevention, sanitation, education, and policy.

Quarantine

Isolation of individuals to prevent the spread of disease, first introduced in Venice during the plague.

Cohort Studies

Epidemiological studies that follow groups over time to determine disease incidence and risk factors.

Social Epidemiology

The study of structural and cultural determinants of health, such as poverty and discrimination.

Causal Inference

The process of identifying whether a relationship between two variables is causal.

Chronic Disease Epidemiology

The study of diseases with long natural histories often caused by multiple factors.

Genetic Disease

Genes as determinants of disease and susceptibility to environment

(e.g. diseases run in families, due to shared genes, behaviours, and environments)

Social Production of Disease

The concept that socio-economic conditions shape risk and prevalence of diseases in populations.

Epidemiology

The study of the distribution/determinants of a disease/condition in populations, factors that influence this distribution, and the use of this study to control health problems

Disease Surveillance

The continued watchfulness over the distribution and trends of disease incidence through systematic collection and evaluation of data.

Risk Factor Epidemiology

The classic approach to chronic disease etiology that estimates associations for one factor at a time.

Chronic Disease

Diseases characterized by

1. long natural history or frequent recurrence

2. having multi-factorial causation

3. etiology other than infection (not always)

Agent-Host-Environment Model

A model that describes the interaction of the agent of disease, the host, and the environment in the epidemiological context. (infectious disease model)

Social Production of Disease

determinants of populations level health → risk regime found in social address and material/social conditions of life

(disparities not often explained by risk factors)

Causal Diagrams

Visual representations that help in understanding and demonstrating causal relationships between factors in epidemiological research.

World Health Organization (WHO) Definition of Epidemiology

The study of the distribution and determinants of health and disease in human populations to enable effective public health planning and evaluation.

Contextual Determinants of Risk

Factors such as social and material conditions that influence an individual's risk for disease.

Disparities in Health

Differences in health outcomes and their determinants between different population groups.

2 Fundamental Assumptions of Epidemiology

1. Disease occurrence is not random. (factors/determinants increase/decrease likelihood of disease)

2. determinants of disease can be identified through the systematic investigation of populations

Models of disease production

hypothetical description of complex entity/process (infectious, chronic, genetic, and social)

multifactorial causation mechanisms

Explain how multiple factors interact to produce disease outcomes. Modern approach to risk factor epidemiology 

Risk factor categories

1. modifiable

2. nonmodifiable