EXAM SERIES
NR576 / NR 576 Midterm
Exam: Differential Diagnosis in
Adult-Gerontology Primary
Care
Comprehensive Exam — Questions and Answers
100 Questions
with Answers and Complete Rationales
01 Scenario-based and direct multiple-choice questions
02 Answers with explanatory rationales
03 Organized by differential diagnosis and primary care competencies
04 Complete questions and answers
2026 EDITION
Questions and Answers • Complete Rationales
, Instructions: This midterm examination contains 100 multiple-choice questions divided into four
sections. Each question has exactly four options labeled A through D and one best answer. Select
the single best option for each question. Rationales are provided after each answer to support
learning and review. The exam assesses differential diagnosis, clinical reasoning, diagnostic test
selection and interpretation, and management planning in adult-gerontology primary care. Allow
approximately 90 seconds per question.
Section 1: Differential Diagnosis Foundations and Clinical Reasoning
Q1. Which statement best defines a differential diagnosis in adult-gerontology primary care?
A. A confirmed list of diagnoses already established for the patient
B. A working list of possible conditions that could explain the patient's presentation
C. A documented treatment plan for a single suspected condition
D. A summary of laboratory and imaging test results
Correct Answer: B. A working list of possible conditions that could explain the patient's
presentation
Rationale: A differential diagnosis is the working list of plausible conditions that could produce the
patient's signs and symptoms; it guides further history, exam, and testing. It is not a confirmed
diagnosis, a treatment plan, or a lab summary.
Q2. Hypothetico-deductive clinical reasoning is best described as:
A. Pattern matching to a single familiar prior case
B. Diagnosing the most common condition first without further testing
C. Asking the patient to choose the most likely diagnosis
D. Generating multiple hypotheses early in the encounter and then testing them through targeted data
collection
Correct Answer: D. Generating multiple hypotheses early in the encounter and then testing them
through targeted data collection
Rationale: Hypothetico-deductive reasoning generates several plausible hypotheses from early cues
and uses focused history, exam, and tests to confirm or refute each hypothesis. Pattern recognition
alone is a different strategy and does not test hypotheses systematically.
,Q3. Anchoring bias in diagnostic reasoning is the tendency to:
A. Overestimate the prevalence of a rare disease in the population
B. Change the diagnosis repeatedly based on each new piece of data
C. Rely exclusively on laboratory values to make a diagnosis
D. Fixate on the initial impression and insufficiently adjust when new data appear
Correct Answer: D. Fixate on the initial impression and insufficiently adjust when new data
appear
Rationale: Anchoring bias describes clinging to the first impression despite disconfirming evidence,
which can delay consideration of alternative diagnoses. It is not the same as overestimating
prevalence or excessive reliance on labs.
Q4. Premature closure in diagnostic reasoning is defined as:
A. Accepting a diagnosis before it has been fully verified and stopping the search for alternatives
B. Closing the electronic medical record chart prematurely
C. Ending a clinical interview as soon as the chief complaint is stated
D. Closing the patient encounter before ordering any laboratory tests
Correct Answer: A. Accepting a diagnosis before it has been fully verified and stopping the
search for alternatives
Rationale: Premature closure occurs when a clinician accepts a diagnosis as final before adequately
verifying it, often overlooking serious alternatives. The other options describe administrative or
workflow actions rather than a cognitive bias.
Q5. Which statement best describes "red flags" in primary care differential diagnosis?
A. Laboratory values that fall within the normal reference range
B. Clinical features suggesting serious or potentially life-threatening conditions that require urgent
evaluation
C. Symptoms that consistently resolve without any intervention
D. Patient-reported symptoms that are always benign and self-limited
Correct Answer: B. Clinical features suggesting serious or potentially life-threatening conditions
that require urgent evaluation
Rationale: Red flags are features (e.g., sudden worst-of-life headache, weight loss, hemoptysis) that
signal potentially serious disease and demand prompt workup. They are not benign symptoms or
normal lab values.
, Q6. The sensitivity of a diagnostic test is best defined as:
A. The probability of a negative test result in patients who do not have the disease
B. The probability of disease given a positive test result
C. The probability of a positive test result in patients who actually have the disease
D. The probability of no disease given a negative test result
Correct Answer: C. The probability of a positive test result in patients who actually have the
disease
Rationale: Sensitivity is the proportion of patients with disease who test positive (true positive rate).
The other definitions correspond to specificity, positive predictive value, and negative predictive value,
respectively.
Q7. A "rule-in" test (a confirmatory test) should ideally have high:
A. Negative predictive value
B. Specificity
C. Sensitivity
D. False-negative rate
Correct Answer: B. Specificity
Rationale: A highly specific test yields few false positives, so a positive result strongly supports the
diagnosis (rule-in). Highly sensitive tests are used to rule out disease because they produce few false
negatives.
Q8. Changes in disease prevalence in the tested population most strongly affect which test
characteristic?
A. Likelihood ratios
B. Sensitivity
C. Predictive values (positive and negative predictive value)
D. Specificity
Correct Answer: C. Predictive values (positive and negative predictive value)
Rationale: Sensitivity, specificity, and likelihood ratios are stable properties of the test, while positive
and negative predictive values shift with disease prevalence. As prevalence rises, positive predictive
value increases and negative predictive value falls.
NR576 / NR 576 Midterm
Exam: Differential Diagnosis in
Adult-Gerontology Primary
Care
Comprehensive Exam — Questions and Answers
100 Questions
with Answers and Complete Rationales
01 Scenario-based and direct multiple-choice questions
02 Answers with explanatory rationales
03 Organized by differential diagnosis and primary care competencies
04 Complete questions and answers
2026 EDITION
Questions and Answers • Complete Rationales
, Instructions: This midterm examination contains 100 multiple-choice questions divided into four
sections. Each question has exactly four options labeled A through D and one best answer. Select
the single best option for each question. Rationales are provided after each answer to support
learning and review. The exam assesses differential diagnosis, clinical reasoning, diagnostic test
selection and interpretation, and management planning in adult-gerontology primary care. Allow
approximately 90 seconds per question.
Section 1: Differential Diagnosis Foundations and Clinical Reasoning
Q1. Which statement best defines a differential diagnosis in adult-gerontology primary care?
A. A confirmed list of diagnoses already established for the patient
B. A working list of possible conditions that could explain the patient's presentation
C. A documented treatment plan for a single suspected condition
D. A summary of laboratory and imaging test results
Correct Answer: B. A working list of possible conditions that could explain the patient's
presentation
Rationale: A differential diagnosis is the working list of plausible conditions that could produce the
patient's signs and symptoms; it guides further history, exam, and testing. It is not a confirmed
diagnosis, a treatment plan, or a lab summary.
Q2. Hypothetico-deductive clinical reasoning is best described as:
A. Pattern matching to a single familiar prior case
B. Diagnosing the most common condition first without further testing
C. Asking the patient to choose the most likely diagnosis
D. Generating multiple hypotheses early in the encounter and then testing them through targeted data
collection
Correct Answer: D. Generating multiple hypotheses early in the encounter and then testing them
through targeted data collection
Rationale: Hypothetico-deductive reasoning generates several plausible hypotheses from early cues
and uses focused history, exam, and tests to confirm or refute each hypothesis. Pattern recognition
alone is a different strategy and does not test hypotheses systematically.
,Q3. Anchoring bias in diagnostic reasoning is the tendency to:
A. Overestimate the prevalence of a rare disease in the population
B. Change the diagnosis repeatedly based on each new piece of data
C. Rely exclusively on laboratory values to make a diagnosis
D. Fixate on the initial impression and insufficiently adjust when new data appear
Correct Answer: D. Fixate on the initial impression and insufficiently adjust when new data
appear
Rationale: Anchoring bias describes clinging to the first impression despite disconfirming evidence,
which can delay consideration of alternative diagnoses. It is not the same as overestimating
prevalence or excessive reliance on labs.
Q4. Premature closure in diagnostic reasoning is defined as:
A. Accepting a diagnosis before it has been fully verified and stopping the search for alternatives
B. Closing the electronic medical record chart prematurely
C. Ending a clinical interview as soon as the chief complaint is stated
D. Closing the patient encounter before ordering any laboratory tests
Correct Answer: A. Accepting a diagnosis before it has been fully verified and stopping the
search for alternatives
Rationale: Premature closure occurs when a clinician accepts a diagnosis as final before adequately
verifying it, often overlooking serious alternatives. The other options describe administrative or
workflow actions rather than a cognitive bias.
Q5. Which statement best describes "red flags" in primary care differential diagnosis?
A. Laboratory values that fall within the normal reference range
B. Clinical features suggesting serious or potentially life-threatening conditions that require urgent
evaluation
C. Symptoms that consistently resolve without any intervention
D. Patient-reported symptoms that are always benign and self-limited
Correct Answer: B. Clinical features suggesting serious or potentially life-threatening conditions
that require urgent evaluation
Rationale: Red flags are features (e.g., sudden worst-of-life headache, weight loss, hemoptysis) that
signal potentially serious disease and demand prompt workup. They are not benign symptoms or
normal lab values.
, Q6. The sensitivity of a diagnostic test is best defined as:
A. The probability of a negative test result in patients who do not have the disease
B. The probability of disease given a positive test result
C. The probability of a positive test result in patients who actually have the disease
D. The probability of no disease given a negative test result
Correct Answer: C. The probability of a positive test result in patients who actually have the
disease
Rationale: Sensitivity is the proportion of patients with disease who test positive (true positive rate).
The other definitions correspond to specificity, positive predictive value, and negative predictive value,
respectively.
Q7. A "rule-in" test (a confirmatory test) should ideally have high:
A. Negative predictive value
B. Specificity
C. Sensitivity
D. False-negative rate
Correct Answer: B. Specificity
Rationale: A highly specific test yields few false positives, so a positive result strongly supports the
diagnosis (rule-in). Highly sensitive tests are used to rule out disease because they produce few false
negatives.
Q8. Changes in disease prevalence in the tested population most strongly affect which test
characteristic?
A. Likelihood ratios
B. Sensitivity
C. Predictive values (positive and negative predictive value)
D. Specificity
Correct Answer: C. Predictive values (positive and negative predictive value)
Rationale: Sensitivity, specificity, and likelihood ratios are stable properties of the test, while positive
and negative predictive values shift with disease prevalence. As prevalence rises, positive predictive
value increases and negative predictive value falls.
