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NSG 550 EXAM 1 – 2026 WILKES DIAGNOSTIC
REASONING COMPLETE (110) CURRENT TESTING
QUESTIONS AND CORRECT ANSWERS WITH DETAILED
RATIONALES.
NSG
Prepare for the NSG 550 Exam 1 – Wilkes Diagnostic Reasoning with this
comprehensive practice resource designed to strengthen your advanced nursing
clinical reasoning skills and exam readiness. It features exam-style questions
covering diagnostic reasoning principles, clinical assessment, health history analysis,
differential diagnosis, evidence-based practice, and foundational decision-making
strategies. Use it to reinforce essential concepts, assess your understanding, and
build confidence before test day. An excellent study aid for Wilkes University nursing
students preparing for the NSG 550 Diagnostic Reasoning Exam 1.
Multiple choice.
SECTION 1: FOUNDATIONS OF DIAGNOSTIC REASONING (Questions 1–20)
Question 1: A 45-year-old presents with chest pain. Using the hypothetico-
deductive model, what is the FIRST step?
A) Order an ECG
B) Generate an initial hypothesis list
C) Perform a complete physical exam
D) Review past medical records
Correct answer: B) Generate an initial hypothesis list
Rationale: The hypothetico-deductive model begins with early hypothesis
generation from limited data, then testing through further questions and
examination .
Question 2: Which heuristic describes the tendency to judge likelihood based
on how easily examples come to mind?
A) Anchoring
B) Availability
, Page 2 of 34
C) Representativeness
D) Confirmation bias
Correct answer: B) Availability
Rationale: The availability heuristic skews probability estimates based on
recent or memorable cases (e.g., the last patient with an MI) .
Question 3: A test with 95% sensitivity means:
A) 95% of people without disease test negative
B) 5% of people with disease test negative
C) 95% of positive tests are true positives
D) The test is highly specific
Correct answer: B) 5% of people with disease test negative
Rationale: Sensitivity = true positive rate. 95% sensitive means 5% false
negatives. It does NOT predict positive predictive value .
Question 4: Pre-test probability is best derived from:
A) The test's cost
B) Clinical judgment and epidemiology
C) Patient insurance status
D) Laboratory reference ranges
Correct answer: B) Clinical judgment and epidemiology
Rationale: Pre-test probability is estimated from patient risk factors,
symptoms, and disease prevalence .
Question 5: You suspect DVT. Which clinical decision rule is most validated?
A) CURB-65
B) Wells Score
C) CHA₂DS₂-VASc
D) HEART Score
Correct answer: B) Wells Score
Rationale: The Wells Score for DVT combines risk factors, clinical signs, and
alternative diagnoses and is the most validated clinical decision rule for DVT .
Question 6: A clinician ignores new information that contradicts their initial
diagnosis. This is:
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A) Ascertainment bias
B) Confirmation bias
C) Framing effect
D) Outcome bias
Correct answer: B) Confirmation bias
Rationale: Confirmation bias involves seeking or favoring information that
confirms one's hypothesis while ignoring contradictory data .
Question 7: Which of the following increases post-test probability the MOST?
A) High sensitivity test, negative
B) High specificity test, positive
C) Low sensitivity test, positive
D) Low specificity test, negative
Correct answer: B) High specificity test, positive
Rationale: SpPIN—a highly Specific test, when Positive, rules IN disease. A
positive result from a specific test dramatically increases post-test
probability .
Question 8: A 70-year-old with fall and leg pain. X-ray negative. You still
suspect fracture. Next step?
A) Discharge with NSAIDs
B) MRI
Correct answer: B) MRI
Rationale: Suspected occult fracture, especially in the elderly, requires
advanced imaging such as MRI, even when X-ray is negative .
SECTION 2: TEST INTERPRETATION & BAYESIAN REASONING (Questions 9–
25)
Question 9: A test's positive predictive value (PPV) increases when:
A) Disease prevalence decreases
B) Disease prevalence increases
C) Test sensitivity decreases
D) Test specificity decreases
, Page 4 of 34
Correct answer: B) Disease prevalence increases
Rationale: PPV rises with disease prevalence. In a low-prevalence
population, even a positive test may have low PPV .
Question 10: LR+ of 8.0 means:
A) Post-test odds increase 8-fold
B) Post-test probability decreases 8%
C) The test is useless
D) Specificity is 80%
Correct answer: A) Post-test odds increase 8-fold
Rationale: LR+ >1 increases probability. An LR+ of 8 is strong, significantly
increasing post-test odds .
Question 11: A negative D-dimer is most useful to rule out DVT in which
patient?
A) Post-op day 1 with leg swelling
B) Low pre-test probability Wells score
C) Active cancer with leg pain
D) Recent major trauma
Correct answer: B) Low pre-test probability Wells score
Rationale: D-dimer only rules out DVT in low pre-test probability patients. In
high-risk patients, a negative D-dimer does not exclude DVT .
Question 12: SpPIN (highly Specific test when Positive rules IN disease)
applies best to:
A) Troponin for MI
B) D-dimer for PE
C) ANA for lupus
D) Western blot for Lyme
Correct answer: A) Troponin for MI
Rationale: Troponin is highly specific for myocardial infarction, making a
positive result extremely useful for ruling in the diagnosis .
Question 13: A 65-year-old with headache. Which finding mandates
neuroimaging?
A) Mild photophobia
NSG 550 EXAM 1 – 2026 WILKES DIAGNOSTIC
REASONING COMPLETE (110) CURRENT TESTING
QUESTIONS AND CORRECT ANSWERS WITH DETAILED
RATIONALES.
NSG
Prepare for the NSG 550 Exam 1 – Wilkes Diagnostic Reasoning with this
comprehensive practice resource designed to strengthen your advanced nursing
clinical reasoning skills and exam readiness. It features exam-style questions
covering diagnostic reasoning principles, clinical assessment, health history analysis,
differential diagnosis, evidence-based practice, and foundational decision-making
strategies. Use it to reinforce essential concepts, assess your understanding, and
build confidence before test day. An excellent study aid for Wilkes University nursing
students preparing for the NSG 550 Diagnostic Reasoning Exam 1.
Multiple choice.
SECTION 1: FOUNDATIONS OF DIAGNOSTIC REASONING (Questions 1–20)
Question 1: A 45-year-old presents with chest pain. Using the hypothetico-
deductive model, what is the FIRST step?
A) Order an ECG
B) Generate an initial hypothesis list
C) Perform a complete physical exam
D) Review past medical records
Correct answer: B) Generate an initial hypothesis list
Rationale: The hypothetico-deductive model begins with early hypothesis
generation from limited data, then testing through further questions and
examination .
Question 2: Which heuristic describes the tendency to judge likelihood based
on how easily examples come to mind?
A) Anchoring
B) Availability
, Page 2 of 34
C) Representativeness
D) Confirmation bias
Correct answer: B) Availability
Rationale: The availability heuristic skews probability estimates based on
recent or memorable cases (e.g., the last patient with an MI) .
Question 3: A test with 95% sensitivity means:
A) 95% of people without disease test negative
B) 5% of people with disease test negative
C) 95% of positive tests are true positives
D) The test is highly specific
Correct answer: B) 5% of people with disease test negative
Rationale: Sensitivity = true positive rate. 95% sensitive means 5% false
negatives. It does NOT predict positive predictive value .
Question 4: Pre-test probability is best derived from:
A) The test's cost
B) Clinical judgment and epidemiology
C) Patient insurance status
D) Laboratory reference ranges
Correct answer: B) Clinical judgment and epidemiology
Rationale: Pre-test probability is estimated from patient risk factors,
symptoms, and disease prevalence .
Question 5: You suspect DVT. Which clinical decision rule is most validated?
A) CURB-65
B) Wells Score
C) CHA₂DS₂-VASc
D) HEART Score
Correct answer: B) Wells Score
Rationale: The Wells Score for DVT combines risk factors, clinical signs, and
alternative diagnoses and is the most validated clinical decision rule for DVT .
Question 6: A clinician ignores new information that contradicts their initial
diagnosis. This is:
, Page 3 of 34
A) Ascertainment bias
B) Confirmation bias
C) Framing effect
D) Outcome bias
Correct answer: B) Confirmation bias
Rationale: Confirmation bias involves seeking or favoring information that
confirms one's hypothesis while ignoring contradictory data .
Question 7: Which of the following increases post-test probability the MOST?
A) High sensitivity test, negative
B) High specificity test, positive
C) Low sensitivity test, positive
D) Low specificity test, negative
Correct answer: B) High specificity test, positive
Rationale: SpPIN—a highly Specific test, when Positive, rules IN disease. A
positive result from a specific test dramatically increases post-test
probability .
Question 8: A 70-year-old with fall and leg pain. X-ray negative. You still
suspect fracture. Next step?
A) Discharge with NSAIDs
B) MRI
Correct answer: B) MRI
Rationale: Suspected occult fracture, especially in the elderly, requires
advanced imaging such as MRI, even when X-ray is negative .
SECTION 2: TEST INTERPRETATION & BAYESIAN REASONING (Questions 9–
25)
Question 9: A test's positive predictive value (PPV) increases when:
A) Disease prevalence decreases
B) Disease prevalence increases
C) Test sensitivity decreases
D) Test specificity decreases
, Page 4 of 34
Correct answer: B) Disease prevalence increases
Rationale: PPV rises with disease prevalence. In a low-prevalence
population, even a positive test may have low PPV .
Question 10: LR+ of 8.0 means:
A) Post-test odds increase 8-fold
B) Post-test probability decreases 8%
C) The test is useless
D) Specificity is 80%
Correct answer: A) Post-test odds increase 8-fold
Rationale: LR+ >1 increases probability. An LR+ of 8 is strong, significantly
increasing post-test odds .
Question 11: A negative D-dimer is most useful to rule out DVT in which
patient?
A) Post-op day 1 with leg swelling
B) Low pre-test probability Wells score
C) Active cancer with leg pain
D) Recent major trauma
Correct answer: B) Low pre-test probability Wells score
Rationale: D-dimer only rules out DVT in low pre-test probability patients. In
high-risk patients, a negative D-dimer does not exclude DVT .
Question 12: SpPIN (highly Specific test when Positive rules IN disease)
applies best to:
A) Troponin for MI
B) D-dimer for PE
C) ANA for lupus
D) Western blot for Lyme
Correct answer: A) Troponin for MI
Rationale: Troponin is highly specific for myocardial infarction, making a
positive result extremely useful for ruling in the diagnosis .
Question 13: A 65-year-old with headache. Which finding mandates
neuroimaging?
A) Mild photophobia
