NR503 Exam 2 Actual Exam Style V1 | NR
503 Population Health, Epidemiology &
Statistical Principles | Chamberlain
1. A clinician is evaluating a new diagnostic test for early-stage Lyme disease. If the test has
high sensitivity, what does this primarily indicate about the test results?
A. The test is very good at identifying those who truly do not have the disease.
B. The test results are highly reproducible and consistent over multiple trials.
C. The test has a high probability of yielding a positive result when the person is healthy.
D. The test will yield very few false negative results among diseased individuals.
Answer: D
Rationale: Sensitivity refers to the proportion of people with the disease who test positive.
A highly sensitive test minimizes false negatives, making it an excellent tool for screening
to ensure no cases are missed. This property is essential when the goal is to identify as
many affected individuals as possible for early intervention.
2. In a study assessing the impact of a new antihypertensive medication, researchers noticed
that the control group was significantly younger than the treatment group. This represents
which epidemiological concept?
A. Information Bias
B. Recall Bias
,C. Confounding
D. Reliability
Answer: C
Rationale: Confounding occurs when an extraneous variable, such as age, is associated
with both the exposure and the outcome. In this scenario, age could independently affect
blood pressure levels, making it difficult to isolate the true effect of the medication.
Researchers must use methods like randomization or stratification to control for these
variables.
3. A public health nurse is reviewing the prevalence of Type 2 Diabetes in a specific county.
How is prevalence fundamentally different from incidence?
A. Prevalence measures the number of new cases, while incidence measures existing cases.
B. Incidence measures the number of new cases over time, while prevalence measures all
existing cases at a point in time.
C. Prevalence is used for infectious diseases, while incidence is only used for chronic
diseases.
D. Incidence is a ratio, whereas prevalence is always a whole number count.
Answer: B
Rationale: Prevalence provides a snapshot of the total disease burden in a population at a
specific time, including both old and new cases. Incidence specifically tracks the rate at
which new cases develop within a susceptible population over a defined period.
,Understanding the difference is vital for resource allocation and evaluating the
effectiveness of prevention programs.
4. When a screening test’s cutoff point is adjusted to increase sensitivity, what usually
happens to the specificity of that test?
A. Specificity will increase proportionally.
B. Specificity will remain unchanged.
C. Specificity will become zero.
D. Specificity will decrease.
Answer: D
Rationale: Sensitivity and specificity often have an inverse relationship when adjusting
cutoff values for continuous data. By lowering the threshold to capture more true positives
(increasing sensitivity), the test is also more likely to capture healthy individuals as
positives. This result leads to an increase in false positives, thereby lowering the specificity
of the test.
5. A researcher conducts a case-control study to examine the link between lung cancer and
radon exposure. What is the primary measure of association used in this study design?
A. Relative Risk (RR)
B. Incidence Density
C. Odds Ratio (OR)
, D. Attributable Risk
Answer: C
Rationale: The Odds Ratio is the standard measure used in case-control studies because
the incidence of disease cannot be directly calculated. It compares the odds of exposure
among those with the disease to the odds of exposure among those without the disease.
This provides an estimate of the strength of the association between the risk factor and the
outcome.
6. Which level of prevention is exemplified by a patient receiving cardiac rehabilitation after
suffering a myocardial infarction?
A. Tertiary Prevention
B. Secondary Prevention
C. Primary Prevention
D. Primordial Prevention
Answer: A
Rationale: Tertiary prevention focuses on managing disease post-diagnosis to slow or stop
disease progression and prevent complications. Cardiac rehabilitation helps patients regain
function and reduce the risk of subsequent events after the initial damage has occurred. It
differs from secondary prevention, which focuses on early detection and screening.
503 Population Health, Epidemiology &
Statistical Principles | Chamberlain
1. A clinician is evaluating a new diagnostic test for early-stage Lyme disease. If the test has
high sensitivity, what does this primarily indicate about the test results?
A. The test is very good at identifying those who truly do not have the disease.
B. The test results are highly reproducible and consistent over multiple trials.
C. The test has a high probability of yielding a positive result when the person is healthy.
D. The test will yield very few false negative results among diseased individuals.
Answer: D
Rationale: Sensitivity refers to the proportion of people with the disease who test positive.
A highly sensitive test minimizes false negatives, making it an excellent tool for screening
to ensure no cases are missed. This property is essential when the goal is to identify as
many affected individuals as possible for early intervention.
2. In a study assessing the impact of a new antihypertensive medication, researchers noticed
that the control group was significantly younger than the treatment group. This represents
which epidemiological concept?
A. Information Bias
B. Recall Bias
,C. Confounding
D. Reliability
Answer: C
Rationale: Confounding occurs when an extraneous variable, such as age, is associated
with both the exposure and the outcome. In this scenario, age could independently affect
blood pressure levels, making it difficult to isolate the true effect of the medication.
Researchers must use methods like randomization or stratification to control for these
variables.
3. A public health nurse is reviewing the prevalence of Type 2 Diabetes in a specific county.
How is prevalence fundamentally different from incidence?
A. Prevalence measures the number of new cases, while incidence measures existing cases.
B. Incidence measures the number of new cases over time, while prevalence measures all
existing cases at a point in time.
C. Prevalence is used for infectious diseases, while incidence is only used for chronic
diseases.
D. Incidence is a ratio, whereas prevalence is always a whole number count.
Answer: B
Rationale: Prevalence provides a snapshot of the total disease burden in a population at a
specific time, including both old and new cases. Incidence specifically tracks the rate at
which new cases develop within a susceptible population over a defined period.
,Understanding the difference is vital for resource allocation and evaluating the
effectiveness of prevention programs.
4. When a screening test’s cutoff point is adjusted to increase sensitivity, what usually
happens to the specificity of that test?
A. Specificity will increase proportionally.
B. Specificity will remain unchanged.
C. Specificity will become zero.
D. Specificity will decrease.
Answer: D
Rationale: Sensitivity and specificity often have an inverse relationship when adjusting
cutoff values for continuous data. By lowering the threshold to capture more true positives
(increasing sensitivity), the test is also more likely to capture healthy individuals as
positives. This result leads to an increase in false positives, thereby lowering the specificity
of the test.
5. A researcher conducts a case-control study to examine the link between lung cancer and
radon exposure. What is the primary measure of association used in this study design?
A. Relative Risk (RR)
B. Incidence Density
C. Odds Ratio (OR)
, D. Attributable Risk
Answer: C
Rationale: The Odds Ratio is the standard measure used in case-control studies because
the incidence of disease cannot be directly calculated. It compares the odds of exposure
among those with the disease to the odds of exposure among those without the disease.
This provides an estimate of the strength of the association between the risk factor and the
outcome.
6. Which level of prevention is exemplified by a patient receiving cardiac rehabilitation after
suffering a myocardial infarction?
A. Tertiary Prevention
B. Secondary Prevention
C. Primary Prevention
D. Primordial Prevention
Answer: A
Rationale: Tertiary prevention focuses on managing disease post-diagnosis to slow or stop
disease progression and prevent complications. Cardiac rehabilitation helps patients regain
function and reduce the risk of subsequent events after the initial damage has occurred. It
differs from secondary prevention, which focuses on early detection and screening.
