NR503 Exam 1 Actual Exam Style V3 | NR
503 Population Health, Epidemiology &
Statistical Principles | Chamberlain
1. A nurse practitioner is reviewing the effectiveness of a new screening tool for early-stage
Alzheimer’s disease. The tool correctly identifies 95% of people who actually have the
disease. Which statistical term best describes this measurement?
A. Specificity
B. Reliability
C. Positive Predictive Value
D. Sensitivity
Correct Answer: D
Expert Explanation: Sensitivity refers to the ability of a test to correctly identify those
with the disease, known as the true positive rate. In this scenario, the tool identifies 95% of
the diseased population. High sensitivity is crucial for screening tests where missing a
diagnosis could lead to significant harm.
2. During a community health assessment, an APRN notices a sudden increase in the number
of new cases of influenza within a two-week period. This measurement is best defined as:
A. Prevalence
B. Incidence
C. Point Prevalence
,D. Attack Rate
Correct Answer: B
Expert Explanation: Incidence measures the number of new cases of a disease that
develop in a population during a specific time period. It differs from prevalence, which
counts all existing cases (both old and new) at a single point in time. Monitoring incidence
is essential for tracking the spread of acute infectious diseases.
3. An APRN is designing a program to reduce the complications of existing Type 2 Diabetes
among elderly patients in a rural clinic. This represents which level of prevention?
A. Primary Prevention
B. Tertiary Prevention
C. Secondary Prevention
D. Primordial Prevention
Correct Answer: B
Expert Explanation: Tertiary prevention focuses on managing disease post-diagnosis to
slow or stop disease progression and prevent complications. Examples include
rehabilitation, support groups, and chronic disease management programs. Primary and
secondary levels focus on prevention and early screening, respectively.
4. When evaluating the results of a clinical trial, the p-value is reported as 0.03. How should
the nurse practitioner interpret this result if the alpha level is set at 0.05?
A. There is a 30% chance that the results occurred by chance.
, B. The results are not statistically significant, and the null hypothesis is accepted.
C. The p-value is too high to determine significance.
D. The results are statistically significant, and the null hypothesis is rejected.
Correct Answer: D
Expert Explanation: A p-value less than the predetermined alpha level (usually 0.05)
indicates that the results are statistically significant. This means the probability that the
results occurred by random chance is low enough to reject the null hypothesis. It suggests
that the observed effect is likely due to the intervention being studied.
5. Which component of the Epidemiological Triad represents the external factors that allow
disease transmission to occur?
A. Host
B. Agent
C. Vector
D. Environment
Correct Answer: D
Expert Explanation: The environment in the epidemiological triad refers to extrinsic
factors that affect the agent and the opportunity for exposure. This can include physical
surroundings, socio-economic factors, or climate. Understanding the environment helps
public health officials design interventions to break the chain of infection.
503 Population Health, Epidemiology &
Statistical Principles | Chamberlain
1. A nurse practitioner is reviewing the effectiveness of a new screening tool for early-stage
Alzheimer’s disease. The tool correctly identifies 95% of people who actually have the
disease. Which statistical term best describes this measurement?
A. Specificity
B. Reliability
C. Positive Predictive Value
D. Sensitivity
Correct Answer: D
Expert Explanation: Sensitivity refers to the ability of a test to correctly identify those
with the disease, known as the true positive rate. In this scenario, the tool identifies 95% of
the diseased population. High sensitivity is crucial for screening tests where missing a
diagnosis could lead to significant harm.
2. During a community health assessment, an APRN notices a sudden increase in the number
of new cases of influenza within a two-week period. This measurement is best defined as:
A. Prevalence
B. Incidence
C. Point Prevalence
,D. Attack Rate
Correct Answer: B
Expert Explanation: Incidence measures the number of new cases of a disease that
develop in a population during a specific time period. It differs from prevalence, which
counts all existing cases (both old and new) at a single point in time. Monitoring incidence
is essential for tracking the spread of acute infectious diseases.
3. An APRN is designing a program to reduce the complications of existing Type 2 Diabetes
among elderly patients in a rural clinic. This represents which level of prevention?
A. Primary Prevention
B. Tertiary Prevention
C. Secondary Prevention
D. Primordial Prevention
Correct Answer: B
Expert Explanation: Tertiary prevention focuses on managing disease post-diagnosis to
slow or stop disease progression and prevent complications. Examples include
rehabilitation, support groups, and chronic disease management programs. Primary and
secondary levels focus on prevention and early screening, respectively.
4. When evaluating the results of a clinical trial, the p-value is reported as 0.03. How should
the nurse practitioner interpret this result if the alpha level is set at 0.05?
A. There is a 30% chance that the results occurred by chance.
, B. The results are not statistically significant, and the null hypothesis is accepted.
C. The p-value is too high to determine significance.
D. The results are statistically significant, and the null hypothesis is rejected.
Correct Answer: D
Expert Explanation: A p-value less than the predetermined alpha level (usually 0.05)
indicates that the results are statistically significant. This means the probability that the
results occurred by random chance is low enough to reject the null hypothesis. It suggests
that the observed effect is likely due to the intervention being studied.
5. Which component of the Epidemiological Triad represents the external factors that allow
disease transmission to occur?
A. Host
B. Agent
C. Vector
D. Environment
Correct Answer: D
Expert Explanation: The environment in the epidemiological triad refers to extrinsic
factors that affect the agent and the opportunity for exposure. This can include physical
surroundings, socio-economic factors, or climate. Understanding the environment helps
public health officials design interventions to break the chain of infection.
