NSG 221 FINAL EXAM: (Latest 2026/2027 Update) Epidemiology,
Environmental Health & Global Health | Q&A | Grade A | 100% Correct
(Verified Answers) – Nursing Program
Subject: NSG 221 – Community & Public Health Nursing
Source: NSG 221 FINAL EXAM Blueprint 2026/2027
Format: Q&A Guide with Rationale | Verified Grade A
1. What is analytic epidemiology?
Correct Answer: Method that investigates the causes of disease by determining why a disease rate is
lower in one population group than in another.
1. Analytic epidemiology tests hypotheses about disease causation (case-control, cohort studies).
2. Identifies risk factors and protective factors.
3. Compares exposed vs unexposed groups to determine association.
2. What is descriptive epidemiology?
Correct Answer: A form of epidemiology that describes a disease according to its person, place, or
time.
1. Descriptive epidemiology answers who, where, when.
2. Generates hypotheses about disease causes.
3. Uses person-place-time variables to describe disease patterns.
3. What is the web of causation?
Correct Answer: A model that can be used to illustrate complex interrelationships of factors interacting
with each other to influence the risk of, or distribution of, health outcomes.
1. Shows multiple interacting causes of chronic disease.
2. Recognizes that health outcomes result from complex interactions.
3. Useful for non-communicable diseases (heart disease, diabetes).
4. What are screening programs?
Correct Answer: A secondary prevention activity that identifies risk factors and diseases in their
earliest stages.
1. Screening detects disease before symptoms appear.
2. Examples: mammography, blood pressure screening, colonoscopy.
3. Benefits must outweigh harms (false positives, overdiagnosis).
, 5. What is surveillance?
Correct Answer: A mechanism for the ongoing collection of health information in a community.
1. Public health surveillance monitors disease trends.
2. Examples: vital statistics, reportable diseases, cancer registries.
3. Provides data for action (outbreak detection, resource allocation).
6. What are the components of the epidemiological triangle (host-agent-environment)?
Correct Answer: Host: a living human or animal organism in which an infectious agent can exist under
natural conditions. Agent: causative factor invading a susceptible host through an environment
favorable to produce disease (biological or chemical). Environment: the accumulation of physical,
social, cultural, economic and political conditions that influence the lives of communities; that which
surrounds the human host and where transmission of an infectious agent is occurring.
1. Host factors: age, sex, genetics, immunity, behavior.
2. Agent factors: bacteria, virus, chemical, radiation, physical force.
3. Environmental factors: physical (climate), biological (vectors), social (crowding).
7. What are rates in epidemiology?
Correct Answer: Arithmetic expressions that allow one to consider a count of an event relative to the
size of the population from which it is extracted.
1. Rates enable comparison across populations of different sizes.
2. Numerator: number of events (cases, deaths).
3. Denominator: population at risk during same time period.
8. What are incidence rates?
Correct Answer: Rates that describe the occurrence of new cases of disease or condition (teen
pregnancy) in a community over a period of time, relative to the size of the population at risk for that
disease or condition during that same period.
1. Incidence = new cases / population at risk over time.
2. Measures risk of developing disease.
3. Important for acute diseases and identifying risk factors.
9. What is prevalence rate?
Correct Answer: The number of all cases of a specific disease or condition (deafness) in a population
at a given point in time, relative to the population at the same point in time.
1. Prevalence = total existing cases / total population at a point in time.
2. Measures burden of disease in population.
3. Affected by incidence and duration of disease.
Environmental Health & Global Health | Q&A | Grade A | 100% Correct
(Verified Answers) – Nursing Program
Subject: NSG 221 – Community & Public Health Nursing
Source: NSG 221 FINAL EXAM Blueprint 2026/2027
Format: Q&A Guide with Rationale | Verified Grade A
1. What is analytic epidemiology?
Correct Answer: Method that investigates the causes of disease by determining why a disease rate is
lower in one population group than in another.
1. Analytic epidemiology tests hypotheses about disease causation (case-control, cohort studies).
2. Identifies risk factors and protective factors.
3. Compares exposed vs unexposed groups to determine association.
2. What is descriptive epidemiology?
Correct Answer: A form of epidemiology that describes a disease according to its person, place, or
time.
1. Descriptive epidemiology answers who, where, when.
2. Generates hypotheses about disease causes.
3. Uses person-place-time variables to describe disease patterns.
3. What is the web of causation?
Correct Answer: A model that can be used to illustrate complex interrelationships of factors interacting
with each other to influence the risk of, or distribution of, health outcomes.
1. Shows multiple interacting causes of chronic disease.
2. Recognizes that health outcomes result from complex interactions.
3. Useful for non-communicable diseases (heart disease, diabetes).
4. What are screening programs?
Correct Answer: A secondary prevention activity that identifies risk factors and diseases in their
earliest stages.
1. Screening detects disease before symptoms appear.
2. Examples: mammography, blood pressure screening, colonoscopy.
3. Benefits must outweigh harms (false positives, overdiagnosis).
, 5. What is surveillance?
Correct Answer: A mechanism for the ongoing collection of health information in a community.
1. Public health surveillance monitors disease trends.
2. Examples: vital statistics, reportable diseases, cancer registries.
3. Provides data for action (outbreak detection, resource allocation).
6. What are the components of the epidemiological triangle (host-agent-environment)?
Correct Answer: Host: a living human or animal organism in which an infectious agent can exist under
natural conditions. Agent: causative factor invading a susceptible host through an environment
favorable to produce disease (biological or chemical). Environment: the accumulation of physical,
social, cultural, economic and political conditions that influence the lives of communities; that which
surrounds the human host and where transmission of an infectious agent is occurring.
1. Host factors: age, sex, genetics, immunity, behavior.
2. Agent factors: bacteria, virus, chemical, radiation, physical force.
3. Environmental factors: physical (climate), biological (vectors), social (crowding).
7. What are rates in epidemiology?
Correct Answer: Arithmetic expressions that allow one to consider a count of an event relative to the
size of the population from which it is extracted.
1. Rates enable comparison across populations of different sizes.
2. Numerator: number of events (cases, deaths).
3. Denominator: population at risk during same time period.
8. What are incidence rates?
Correct Answer: Rates that describe the occurrence of new cases of disease or condition (teen
pregnancy) in a community over a period of time, relative to the size of the population at risk for that
disease or condition during that same period.
1. Incidence = new cases / population at risk over time.
2. Measures risk of developing disease.
3. Important for acute diseases and identifying risk factors.
9. What is prevalence rate?
Correct Answer: The number of all cases of a specific disease or condition (deafness) in a population
at a given point in time, relative to the population at the same point in time.
1. Prevalence = total existing cases / total population at a point in time.
2. Measures burden of disease in population.
3. Affected by incidence and duration of disease.
