Key Concepts of Epidemiology

Which statements about epidemiological associations are accurate? Select all that apply. -Associations establish causation in epidemiology. -Associations may indicate cause-and-effect relationships. -Associations help target disease prevention and control activities. -Associations guide additional research into the causes of disease. -Associations are insufficient evidence to guide public health activities.

-Associations may indicate cause-and-effect relationships. Rationale: Epidemiological associations do not establish causation in epidemiology, but associations guide additional research into the causes of disease. In this way, an association may indicate cause-and-effect relationships. -Associations help target disease prevention and control activities. Rationale: Identifying associations help public health officials target public health prevention and control activities. -Associations guide additional research into the causes of disease. Rationale: Associations highlight notable connections between personal characteristics of individuals with a disease to the likelihood of acquiring that specific disease and, therefore, guide additional research into the causes of disease.

Which definition describes epidemiologic determinants? -The basic science of public health -Distribution of disease by frequency and pattern -Causes of disease or other factors that influence health -Preventative measures for the control of disease or illness

-Causes of disease or other factors that influence health Rationale: Epidemiologic determinants are the causes of disease or other factors that influence health.

Which function summarizes the goal of descriptive epidemiology? -Identify causes of disease -Establish health data associations -Determine disease transmission routes -Communicate aspects of disease distribution

-Communicate aspects of disease distribution Rationale: Descriptive epidemiology focuses on describing, or communicating, certain aspects of disease distribution. Standard descriptive characteristics include distribution by time, place, and person.

Two branches of epidemiology

-Descriptive epidemiology: the study of the amount and distribution of health and health problems within a population. -Analytic epidemiology: investigates a disease and contributing factors by time, place, and person.

Which elements comprise the epidemiological triangle model of disease causality? Select all that apply. -Host -Agent -Exposure -Genetic core -Environment

-Host Rationale: Host is one of the three elements of the epidemiological triangle. Host refers to the human who can get the disease. -Agent Rationale: Agent is one of the three elements of the epidemiological triangle. Agent refers to an infectious microorganism or pathogen, such as a virus, bacterium, parasite, or other microbe, or chemical and physical causes of disease or injury. -Environment Rationale: Environment is one of the three elements of the epidemiological triangle. Environment refers to extrinsic factors that affect the agent and the opportunity for exposure.

Which core terms define the distribution of health events observed within a population? Select all that apply. -Spread -Pattern -Intensity -Magnitude -Frequency

-Pattern Rationale: Pattern is a defining term of epidemiologic distribution. Pattern refers to the occurrence of health-related events by time, place, and person. -Frequency Rationale: Frequency is a defining term of epidemiologic distribution. It refers to the number of health events and the relationship of that number to the size of the population.

What is the function of a comparison group in analytic epidemiology? -Eliminates the need for standardized rate reporting -Sets standards for reasonable disease rates within a population -Provides baseline data to quantify the association between suspected causes and effects -Provides epidemiologists with adequate evidence to establish causality between determinants and health outcomes

-Provides baseline data to quantify the association between suspected causes and effects Rationale: Comparison groups provide data to quantify the association between suspected causes and effects, and test hypotheses about specific determinants as causal agents of disease.

What is the main purpose of epidemiologic surveillance? -Identifies causes of disease -Advocates for epidemiologic research -Provides data for making public health decisions -Builds relationships among local public health agencies

-Provides data for making public health decisions Rationale: Surveillance is the purposeful and on-going acquisition, interpretation, and synthesis of data for decision making about interventions conducted in local and national public health programs.

In descriptive epidemiology, health event data is commonly organized and communicated according to which defining variables? Select all that apply. -Time -Place -Cause -Person -Association

-Time Rationale: Time patterns may be annual, seasonal, weekly, daily, hourly, weekday versus weekend, or any other breakdown of time that may influence disease or injury occurrence. -Place Rationale: Place patterns include geographic variation, urban/rural differences, and location of work sites or schools. -Person Rationale: Personal patterns include demographic factors which may be related to risk of illness, injury, or disability such as age, sex, marital status, and socioeconomic status, as well as behaviors and environmental exposures.

When is the wheel model of disease causation more applicable than the epidemiological triangle model? -When describing epidemiologic distribution -When analyzing diseases with high occurrence rates -When analyzing communicable diseases in a population -When analyzing complex chronic conditions with multiple causes

-When analyzing complex chronic conditions with multiple causes Rationale: The wheel model of human-environment interaction is more useful for analyzing complex chronic conditions and identifying factors that are amenable to intervention because it subscribes to multiple-causation rather than single-causation disease theory.

Match the public health functions to their branch of epidemiology. 1) Health event surveillance and monitoring 2) Investigation of causes and factors contributing to health events a) Descriptive epidemiology b) Analytic epidemiology

1) a 2) b

Match the epidemiologic model of disease causation to the health event it best represents. 1) Infectious disease outbreak in a community 2) Increase in a particular chronic condition in a community a) Wheel model of human-environment interaction b) Epidemiological triangle

1) b 2) a

The Wheel Model

The multiplicity of host and environmental interactions (multiple-causation instead of single causation). More useful for analyzing complex chronic conditions.

Epidemiological triangle

Traditional model for infectious disease investigation.

Why is it useful to utilize a standardized frequency rate in epidemiologic surveillance? 1) Standardized frequency rates are required to assess the accuracy of epidemiologic data. 2) The use of standardized frequency rates eliminates the need to establish patterns within epidemiologic data. 3) Standardized frequency rates allow epidemiologists to compare disease occurrence across different populations. 4) Calculation of standardized frequency rates is mathematically less complex than reporting actual numbers of disease cases.

3) Standardized frequency rates allow epidemiologists to compare disease occurrence across different populations. Rationale: Frequency refers not only to the number of health events, but also to the relationship of that number to the size of the population. Using a standardized frequency rate to allows epidemiologists to easily compare disease occurrence rates across different populations.