Epidemiology and Its Role in Public Health

Population

The focus of epidemiology, studying the distribution and determinants of health-related phenomena in human populations to address health problems.

Descriptive Epidemiology

The branch of epidemiology that focuses on describing the distribution of diseases by person, place, and time to track disease occurrence.

Epidemiology

The study of the distribution and determinants of health-related phenomena in human populations and the application of this study to control health problems.

Public Health

A multidisciplinary field aiming to promote the health of the population through organized community efforts, focusing on disease prevention and health promotion.

Surveillance

The concept involving monitoring, collection, analysis, and dissemination of data related to a specific health event for action.

Prevalence vs. Incidence

Prevalence refers to the proportion of a population with a specific condition at a given time, while incidence is the rate of new cases in a population over a specified period.

Mortality Measures

Different measures used to quantify death rates in a population, providing insights into the frequency and patterns of deaths.

Distribution

The study of the patterns and determinants of health-related phenomena in human populations and the application of this study to control health issues.

Determinants

Factors or events that influence changes in health-related phenomena, also known as exposures.

Morbidity

Illness resulting from a specific disease or health condition within a population.

Key Activities in Epidemiology

Include meticulous description, comparison of groups, investigation, interpretation, understanding data limitations, drawing causal inferences, and creating interventions.

Routinely Available Data

Data collected, analyzed, and presented to assess population health or disease patterns, often used to observe, describe, and establish baseline characteristics.

Value of Routinely Available Data

Includes availability at low cost, helpful in generating hypotheses, identifying research areas, and providing baseline health status information.

Limitations of Routinely Available Data

May lack completeness, not always up-to-date, subject to political influences, and may not collect all variables of interest.

Questions about Routinely Available Data

Inquire (questionaire) about data collection, purpose, completeness, case definition, accuracy, and population at risk definition.

Routinely Available Data Sources

1. Demographic data
2. Mortality data
3. Morbidity data

Census Data

Main source of demographic data that informs legislation, diplomacy, and resource allocation.

Civil Registration and Vital Statistics

Records including birth, death, and marriage data allowing international comparison of fertility and mortality.

Vital Records Usage - Individual

Includes proof of identity, age, place of birth, citizenship, parentage through population registries, identity card systems, and social programs.

Vital Records Usage - Death

Provides evidence of death for heirs, insurance claims, estate probate, and supports genealogical research.

Morbidity Data

Includes hospital databases, primary care records, disease registers, and household surveys on disease occurrence and disability.

Data on Health-Related Behavior and Risk Factors

Includes variables like height, weight, BMI, smoking status, cholesterol, blood pressure, and vaccination coverage.

Incidence

The occurrence of new cases of a disease in a population at risk over a specific time period.

Prevalence

Measures all cases of a disease at a point or over a period, indicating disease spread in the population.

Crude Death Rate

Total deaths in a year per 100,000 total population.

Specific Mortality Rate

Death rate within a specific subgroup of the population, such as a certain age range.

Case Fatality Rate

Proportion of individuals with a disease who die from it, indicating disease severity.