ATI RN Community Health Proctored
Exam 2025/2026 – 100% Correct
Answers with Rationales
Epidemiology (Questions 1-12)
Question 1
A community health nurse is conducting a needs assessment in a rural area with high rates of
chronic disease. Which epidemiological measure best identifies the total number of existing
cases of diabetes in the population at a given time?
A. Incidence rate
B. Prevalence rate
C. Attack rate
D. Mortality rate
B. Prevalence rate
Rationale: Prevalence rate measures the proportion of a population with a condition at a
specific time (e.g., % with diabetes), aiding resource allocation for chronic care. In community
health, this informs screening programs; incidence tracks new cases, attack rates outbreaks,
and mortality deaths.
Question 2
During an influenza outbreak, the nurse tracks 50 new cases in a population of 1,000 over one
month. What is the incidence rate per 1,000?
A. 5%
B. 50 per 1,000
C. 0.05%
D. 500 per 1,000
B. 50 per 1,000
,Rationale: Incidence = (new cases / population at risk) × 1,000 = (,000) × 1,000 = 50. This
quantifies outbreak burden, guiding vaccination drives; per CDC 2025, high incidence
(>20/1,000) prompts public health alerts.
Question 3
A nurse analyzes data showing a cluster of lung cancer cases near a factory. What study design
would best investigate causation?
A. Case-control study
B. Cross-sectional survey
C. Cohort study
D. Randomized controlled trial
A. Case-control study
Rationale: Case-control compares exposed/unexposed retrospectively for odds ratios, efficient
for rare outcomes like cancer. In epidemiology, it's ideal for environmental links; cohort follows
forward, cross-sectional snapshots prevalence.
Question 4
In a community with rising obesity, the nurse calculates the case-fatality rate for related
comorbidities. What does this measure?
A. Proportion of deaths among diagnosed cases
B. New cases per year
C. Total cases present
D. Risk factors distribution
A. Proportion of deaths among diagnosed cases
Rationale: Case-fatality rate = (deaths from disease / diagnosed cases) × 100, assessing
severity (e.g., 5% for obesity-linked CVD). Guides interventions like education; per WHO 2026,
monitors pandemic impacts.
Question 5
A nurse uses the epidemiological triangle to address teen pregnancy. What represents the
agent in this model?
A. Peer pressure and media
B. Biological capacity for reproduction
C. Family socioeconomic status
, D. Access to contraception
B. Biological capacity for reproduction
Rationale: The agent is the cause (reproductive biology in youth); host (teens), environment
(social factors) interact. Community nursing applies this for targeted programs like school
clinics, per Healthy People 2030.
Question 6
During surveillance for tuberculosis, the nurse reports a 10% increase in cases. What level of
prevention is this?
A. Primary: Vaccination campaigns
B. Secondary: Screening and contact tracing
C. Tertiary: Treatment adherence support
D. Quaternary: Policy advocacy
B. Secondary: Screening and contact tracing
Rationale: Secondary prevention detects/ treats early (e.g., Mantoux tests); surveillance
identifies trends for intervention. Epidemiology distinguishes levels: Primary avoids, tertiary
mitigates damage, per CDC tiers.
Question 7
A community survey reveals 20% depression prevalence among elderly. What sampling method
ensures representativeness?
A. Convenience sampling
B. Stratified random sampling
C. Snowball sampling
D. Purposive sampling
B. Stratified random sampling
Rationale: Stratified divides population (e.g., by age groups) for proportional random selection,
reducing bias. In community epi, this validates prevalence for funding; convenience risks
underrepresentation.
Question 8
The nurse evaluates a water contamination outbreak with 100 cases/5,000 exposed. What is
the relative risk?
Exam 2025/2026 – 100% Correct
Answers with Rationales
Epidemiology (Questions 1-12)
Question 1
A community health nurse is conducting a needs assessment in a rural area with high rates of
chronic disease. Which epidemiological measure best identifies the total number of existing
cases of diabetes in the population at a given time?
A. Incidence rate
B. Prevalence rate
C. Attack rate
D. Mortality rate
B. Prevalence rate
Rationale: Prevalence rate measures the proportion of a population with a condition at a
specific time (e.g., % with diabetes), aiding resource allocation for chronic care. In community
health, this informs screening programs; incidence tracks new cases, attack rates outbreaks,
and mortality deaths.
Question 2
During an influenza outbreak, the nurse tracks 50 new cases in a population of 1,000 over one
month. What is the incidence rate per 1,000?
A. 5%
B. 50 per 1,000
C. 0.05%
D. 500 per 1,000
B. 50 per 1,000
,Rationale: Incidence = (new cases / population at risk) × 1,000 = (,000) × 1,000 = 50. This
quantifies outbreak burden, guiding vaccination drives; per CDC 2025, high incidence
(>20/1,000) prompts public health alerts.
Question 3
A nurse analyzes data showing a cluster of lung cancer cases near a factory. What study design
would best investigate causation?
A. Case-control study
B. Cross-sectional survey
C. Cohort study
D. Randomized controlled trial
A. Case-control study
Rationale: Case-control compares exposed/unexposed retrospectively for odds ratios, efficient
for rare outcomes like cancer. In epidemiology, it's ideal for environmental links; cohort follows
forward, cross-sectional snapshots prevalence.
Question 4
In a community with rising obesity, the nurse calculates the case-fatality rate for related
comorbidities. What does this measure?
A. Proportion of deaths among diagnosed cases
B. New cases per year
C. Total cases present
D. Risk factors distribution
A. Proportion of deaths among diagnosed cases
Rationale: Case-fatality rate = (deaths from disease / diagnosed cases) × 100, assessing
severity (e.g., 5% for obesity-linked CVD). Guides interventions like education; per WHO 2026,
monitors pandemic impacts.
Question 5
A nurse uses the epidemiological triangle to address teen pregnancy. What represents the
agent in this model?
A. Peer pressure and media
B. Biological capacity for reproduction
C. Family socioeconomic status
, D. Access to contraception
B. Biological capacity for reproduction
Rationale: The agent is the cause (reproductive biology in youth); host (teens), environment
(social factors) interact. Community nursing applies this for targeted programs like school
clinics, per Healthy People 2030.
Question 6
During surveillance for tuberculosis, the nurse reports a 10% increase in cases. What level of
prevention is this?
A. Primary: Vaccination campaigns
B. Secondary: Screening and contact tracing
C. Tertiary: Treatment adherence support
D. Quaternary: Policy advocacy
B. Secondary: Screening and contact tracing
Rationale: Secondary prevention detects/ treats early (e.g., Mantoux tests); surveillance
identifies trends for intervention. Epidemiology distinguishes levels: Primary avoids, tertiary
mitigates damage, per CDC tiers.
Question 7
A community survey reveals 20% depression prevalence among elderly. What sampling method
ensures representativeness?
A. Convenience sampling
B. Stratified random sampling
C. Snowball sampling
D. Purposive sampling
B. Stratified random sampling
Rationale: Stratified divides population (e.g., by age groups) for proportional random selection,
reducing bias. In community epi, this validates prevalence for funding; convenience risks
underrepresentation.
Question 8
The nurse evaluates a water contamination outbreak with 100 cases/5,000 exposed. What is
the relative risk?
