DO Diagnostic Reasoning and Evidence-Based Medicine 3

Question 1

The likelihood ratio positive (LR+) for a diagnostic test is calculated as:

Accepted Answer

Sensitivity / (1 - Specificity)

Answer

LR+ = sensitivity / (1 – specificity), quantifying how much a positive test result increases the odds of disease relative to the pre-test probability.

Question 2

When interpreting diagnostic tests, which situation should prompt concern about verification bias?

Accepted Answer

Disease status confirmed only in patients with positive screening tests

Answer

Verification bias occurs when gold standard testing is applied selectively (e.g., only to positive screens), overestimating sensitivity and underestimating specificity.

Question 3

In clinical practice, a decision threshold (test threshold) represents the probability at which:

Accepted Answer

Testing is warranted based on pre-test probability and test risk/benefit

Answer

The test threshold is the pre-test probability below which testing is unnecessary, while the treatment threshold is the probability above which treatment proceeds without testing.

Question 4

Which statistical test is most appropriate for comparing means of a continuous variable between two independent groups with normally distributed data?

Accepted Answer

Independent samples t-test

Answer

The independent samples t-test compares means of normally distributed continuous variables between two independent groups to test for statistically significant differences.

Question 5

Premature closure in diagnostic reasoning is best described as:

Accepted Answer

Accepting a diagnosis before all relevant information has been gathered

Answer

Premature closure stops diagnostic inquiry once a plausible diagnosis is found, missing alternative or comorbid diagnoses that would have been revealed by further evaluation.

DO - Doctor of Osteopathy Practice Test

DO - Doctor of Osteopathy Practice Test

DO Diagnostic Reasoning and Evidence-Based Medicine 3