PH450: Epidemiology Terms

Ratio

Comparison of two quantities

Covariates

Confounding variables and effect modifiers

Fruits and Vegetables

Consumption of fruits and vegetables as a dietary factor.

Prevalence Studies

Cross-sectional studies that assess the prevalence of a health problem in a defined population at one particular time.

National Ambulatory Medical Care Survey

Cross-sectional survey conducted by the National Center for Health Statistics.

National Health Interview Survey (NHIS)

Cross-sectional survey conducted by the National Center for Health Statistics.

National Health and Nutrition Examination Survey (NHANES)

Cross-sectional survey conducted by the National Center for Health Statistics.

National Hospital Discharge Survey

Cross-sectional survey conducted by the National Center for Health Statistics.

National Nursing Home Survey

Cross-sectional survey conducted by the National Center for Health Statistics.

Attributable Risk

Excess disease risk associated with exposure among those who are exposed.

Exposures and Risk Behaviors

Factors that contribute to health issues, such as nutrition, exercise, immunizations, and substance use.

Quality of the Data

Factors to consider when evaluating data, such as population coverage, completeness, accuracy, and availability.

Epidemiologic measures

Frequency, public health impact, strength of associations

Exposed group

Group of individuals with a specific exposure.

Non-exposed group

Group of individuals without a specific exposure.

Population of Interest

Group of people with a common characteristic

Comparison group

Group usually not exposed used to evaluate disease occurrence in an exposed group.

HIPAA

Health Insurance Portability and Accountability Act of 1996, which protects the privacy and security of health information.

Natural History of Disease

Incidence and prevalence over time

Data Sources

Information on health status collected by governmental and non-governmental agencies.

Sun Exposure

Level of exposure to sunlight.

Prevalence

Measures existence of current disease

Incidence

Measures occurrence of new disease

Fixed population

Membership is semi-permanent or unchanging

Dynamic population

Membership is transient or open

NCHS

National Center for Health Statistics, a CDC agency that collects and analyzes health data.

NHANES

National Health and Nutrition Examination Survey, which collects survey and clinical data on the U.S. population.

Convenience Sampling

Non-random sampling method based on convenience or availability.

Mortality

Number of deaths in a population.

Prevalence Rate

Number of existing cases per population

Cumulative Incidence

Number of new cases in a specified time period

Incidence Rate

Number of new cases of a disease per unit of person-time.

Incidence rate

Number of new cases of a disease per unit of person-time.

Incidence Rate

Number of new cases per person-time of observation

Rates

Numerator and denominator with units

Proportions/Percentages

Numerator and denominator, dimensionless

Family History of Breast Cancer

Presence of breast cancer in first or second degree relatives.

Point Prevalence

Prevalence at a certain moment in time

Period Prevalence

Prevalence during a specified period of time

Simple Random Sampling

Probability sampling method where each individual has an equal chance of being selected.

Systematic Random Sampling

Probability sampling method where individuals are selected at regular intervals from a list or sequence.

Clustered Sampling

Probability sampling method where the population is divided into clusters and individuals are randomly selected from each cluster.

Stratified Random Sampling

Probability sampling method where the population is divided into strata and individuals are randomly selected from each stratum.

Attributable Proportion

Proportion of disease that would be prevented by eliminating the exposure in the exposed group.

Population Attributable Proportion

Proportion of disease that would be prevented by eliminating the exposure in the total population.

Cumulative incidence

Proportion of individuals who develop a disease over a specified time period.

Prevalence

Proportion of individuals with a disease at a specific point in time.

Age-specific Rate

Rate restricted to specific age group

Risk Ratio

Ratio of disease risk between exposed and non-exposed groups.

Sex ratios

Ratio of males to females

State cancer registries

Registries at the state level that collect information on cancer cases and outcomes.

State trauma registries

Registries at the state level that collect information on traumatic injuries and outcomes.

Outcomes

Results of health conditions, including deaths, illnesses, injuries, and birth defects.

Probability Sampling

Sampling method where each individual in the population has an equal chance of being selected.

Dependent

Severe pulmonary disease, disease/outcome

International / Global

Sources of health data from international organizations, such as the World Health Organization (WHO).

Measures of Association

Statistical measures used to quantify the relationship between exposure and disease.

Logistic Regression

Statistical method used to control for confounding variables in the analysis.

Chi-Square Test

Statistical test used to determine if there is an association between two variables.

Cross-sectional

Study design assessing exposure and outcome at one moment in time.

Epidemiology

Study of disease occurrence and distribution in populations.

Public Health Surveillance Programs

Systematic collection of information on diseases, risk factors, and health behaviors for monitoring and control.

Prevalence Difference (PD)

The difference in prevalence of a health problem between two groups.

Population

The entire group of individuals being studied.

Odds Ratio (OR)

The likelihood of having a disease in one group compared to another group.

2020 Census

The most recent census that collected information on household composition, demographics, and socioeconomic factors.

Prevalence

The proportion of individuals in a population who have a specific health problem at a given time.

Prevalence Ratio (PR)

The ratio of the prevalence of a health problem in one group compared to another group.

Utilization

The use of healthcare services, including hospitalizations and visits to physicians and emergency departments.

Relative Risk

Another term for risk ratio, quantifies the strength of the relationship between exposure and disease.

Etiological Fraction

Another term for attributable proportion, assesses the effectiveness of prevention/treatment in the exposed group.

Wide-Ranging Online Data for Epidemiological Research (WONDER)

An online database from the CDC that provides access to a wide range of health data.

Parameter

A characteristic of the population being studied.

Statistic

A characteristic of the sample being studied.

Census

A constitutionally mandated count of the U.S. population every 10 years, used for demographic measures.

Birth Certificate

A document that records information about a person's birth, including cause of death for infant mortality statistics.

Death Certificate

A document that records information about a person's death, including cause of death and contributing factors.

NCI Surveillance, Epidemiology and End Results

A program that uses cancer registries to monitor cancer trends and guide cancer control programs.

American Community Survey

A sample-based survey conducted between census years to gather socioeconomic information.

Sample

A subset of the population used to represent the entire group.

CDC Behavioral Risk Factor Surveillance System

A survey that collects information on health-related risk factors, chronic conditions, and preventive services.

Health Interview Survey

A survey that collects information on health-related topics, such as dental visits and poverty levels.

CDC National Notifiable Disease Surveillance System

A system that requires reporting of certain diseases to the state and voluntary reporting to the CDC.

AIDS

Acquired Immunodeficiency Syndrome

Normal weight

BMI between 18.5 and 24.9, indicating a healthy body weight.

Overweight

BMI between 25.0 and 29.9, indicating higher than normal body weight.

Underweight

BMI less than 18.5, indicating lower than normal body weight.

Obese

BMI of 30.0 or higher, indicating significantly higher than normal body weight.

Crude Rate

Basic rate for the entire population

BMI

Body mass index, a measure of body fat based on height and weight.

Registries

Centralized databases for collecting information about specific diseases, such as cancer.

Vital Statistics

Data on births, deaths, marriages, and divorces, including causes of death and demographic information.

Magnitude and Distribution

Describing the extent and pattern of a health problem in a population.

Risk Difference

Difference in disease risk between exposed and non-exposed groups.

Population Risk Difference

Disease burden associated with exposure among the population.

Absolute Risk

Disease risk in a specific group.

Inference

Drawing conclusions about the population based on the sample data.

Apparent drop in death rates

Due to changes in ICD coding

Independent

Electronic-cigarettes, risk factor/exposure

Study Variables

Variables needed for the study