WILKES NSG 550 EXAM 2 - DIAGNOSTIC
REASONING QUESTIONS AND
ANSWERS
1. A test with high sensitivity is most useful for which of the following clinical purposes?
A. Ruling out a diagnosis when the test is negative.
B. Ruling in a diagnosis when the test is positive.
C. Confirming the presence of a rare disease.
D. Determining the exact etiology of a condition.
Answer: A
Conceptual Explanation: High sensitivity means the test has a low false-negative rate. The
mnemonic SnNout (Sensitivity, Negative, rule out) indicates that a negative result in a
highly sensitive test helps rule out the disease.
2. Which statistical value represents the proportion of patients with a disease who test
positive?
A. Specificity
B. Positive Predictive Value
,C. Sensitivity
D. Negative Predictive Value
Answer: C
Conceptual Explanation: Sensitivity is defined as the ability of a test to correctly identify
those with the disease (True Positive Rate).
3. A clinician relies heavily on the first piece of information encountered during a patient
assessment, failing to adjust their diagnosis as new data arrives. This is an example of:
A. Anchoring Bias
B. Confirmation Bias
C. Availability Heuristic
D. Premature Closure
Answer: A
Conceptual Explanation: Anchoring bias is the tendency to fixate on initial information
and fail to adequately adjust for subsequent information.
4. In the context of diagnostic testing, what happens to the Positive Predictive Value (PPV) as
the prevalence of the disease in the population increases?
A. PPV increases.
B. PPV decreases.
C. PPV remains constant.
, D. PPV becomes equal to sensitivity.
Answer: A
Conceptual Explanation: PPV is highly dependent on prevalence. As the prevalence of a
disease increases in a population, the probability that a positive test result is a true positive
also increases.
5. Which of the following describes ‘System 1’ thinking in the Dual Process Theory of clinical
reasoning?
A. Analytical, slow, and effortful.
B. Hypothetico-deductive and systematic.
C. Rule-based and logically demanding.
D. Fast, intuitive, and pattern-based.
Answer: D
Conceptual Explanation: System 1 is fast, automatic, and intuitive, often relying on
pattern recognition or heuristics, whereas System 2 is slow, analytical, and deliberate.
6. A Likelihood Ratio (LR) of 1.0 indicates that:
A. The test provides no useful information to change the probability.
B. The test significantly decreases the post-test probability.
C. The test significantly increases the post-test probability.
D. The test is the gold standard for diagnosis.
REASONING QUESTIONS AND
ANSWERS
1. A test with high sensitivity is most useful for which of the following clinical purposes?
A. Ruling out a diagnosis when the test is negative.
B. Ruling in a diagnosis when the test is positive.
C. Confirming the presence of a rare disease.
D. Determining the exact etiology of a condition.
Answer: A
Conceptual Explanation: High sensitivity means the test has a low false-negative rate. The
mnemonic SnNout (Sensitivity, Negative, rule out) indicates that a negative result in a
highly sensitive test helps rule out the disease.
2. Which statistical value represents the proportion of patients with a disease who test
positive?
A. Specificity
B. Positive Predictive Value
,C. Sensitivity
D. Negative Predictive Value
Answer: C
Conceptual Explanation: Sensitivity is defined as the ability of a test to correctly identify
those with the disease (True Positive Rate).
3. A clinician relies heavily on the first piece of information encountered during a patient
assessment, failing to adjust their diagnosis as new data arrives. This is an example of:
A. Anchoring Bias
B. Confirmation Bias
C. Availability Heuristic
D. Premature Closure
Answer: A
Conceptual Explanation: Anchoring bias is the tendency to fixate on initial information
and fail to adequately adjust for subsequent information.
4. In the context of diagnostic testing, what happens to the Positive Predictive Value (PPV) as
the prevalence of the disease in the population increases?
A. PPV increases.
B. PPV decreases.
C. PPV remains constant.
, D. PPV becomes equal to sensitivity.
Answer: A
Conceptual Explanation: PPV is highly dependent on prevalence. As the prevalence of a
disease increases in a population, the probability that a positive test result is a true positive
also increases.
5. Which of the following describes ‘System 1’ thinking in the Dual Process Theory of clinical
reasoning?
A. Analytical, slow, and effortful.
B. Hypothetico-deductive and systematic.
C. Rule-based and logically demanding.
D. Fast, intuitive, and pattern-based.
Answer: D
Conceptual Explanation: System 1 is fast, automatic, and intuitive, often relying on
pattern recognition or heuristics, whereas System 2 is slow, analytical, and deliberate.
6. A Likelihood Ratio (LR) of 1.0 indicates that:
A. The test provides no useful information to change the probability.
B. The test significantly decreases the post-test probability.
C. The test significantly increases the post-test probability.
D. The test is the gold standard for diagnosis.
