FREE BCACP Clinical Literature Interpretation Questions and Answers

Question 1

A pharmacist reviews a randomized controlled trial comparing a new lipid-lowering agent to placebo.
The primary endpoint was major adverse cardiovascular events (MACE).
The event rate in the placebo group was 12% and in the new agent group was 8%.
What is the number needed to treat (NNT) to prevent one MACE?

Accepted Answer

25

Answer

4

Answer

8

Answer

12

Question 2

A clinical trial evaluates a new medication for stroke prevention in patients with atrial fibrillation. The results for the primary outcome of ischemic stroke are reported as a Hazard Ratio (HR) of 0.80 with a 95% Confidence Interval (CI) of 0.65 to 1.05. Which of the following is the most accurate interpretation of this finding?

Accepted Answer

The result is not statistically significant.

Answer

The new medication is superior to the comparator for stroke prevention.

Answer

The new medication is inferior to the comparator for stroke prevention.

Answer

The p-value must be less than 0.05.

Question 3

Researchers wish to determine if exposure to a certain workplace chemical is associated with the development of a rare form of cancer. They identify a group of individuals with the cancer (cases) and a similar group without the cancer (controls). They then look back in time, using work history records, to determine the rate of chemical exposure in each group. Which study design does this describe?

Accepted Answer

Case-Control Study

Answer

Randomized Controlled Trial

Answer

Prospective Cohort Study

Answer

Cross-Sectional Study

Question 4

A large, multicenter randomized controlled trial is analyzed using the intention-to-treat (ITT) principle. What is the primary advantage of using an ITT analysis?

Accepted Answer

It preserves the benefits of randomization and reflects a more realistic measure of treatment effectiveness.

Answer

It provides the most accurate estimate of the drug's efficacy when taken perfectly as prescribed.

Answer

It increases the statistical power by excluding non-adherent patients from the final analysis.

Answer

It is the preferred method for non-inferiority trials to avoid bias towards the null.

Question 5

A clinical trial for a new heart failure medication reports a statistically significant reduction in its primary composite endpoint of 'cardiovascular death, hospitalization for heart failure, or urgent heart failure visit.' An analysis of the individual components reveals the benefit was driven almost exclusively by a reduction in urgent heart failure visits, with no significant difference in CV death or hospitalizations. What is the most appropriate clinical interpretation?

Accepted Answer

The benefit of the drug is primarily related to reducing less severe events like urgent heart failure visits.

Answer

The drug is proven effective at reducing mortality and hospitalizations in patients with heart failure.

Answer

The composite endpoint is invalid and the study results should be disregarded entirely.

Answer

The drug is likely to show a mortality benefit if the trial is extended for a longer duration.

Question 6

In a clinical study, researchers conclude that a new therapy is superior to placebo (p=0.04). In reality, however, no true difference exists between the therapy and placebo. What type of error has occurred?

Accepted Answer

Type I error

Answer

Type II error

Answer

Confounding bias

Answer

Selection bias