BMAT Research & Evidence-Based Practice 4

Question 1

A researcher reports a p-value of 0.03 for a primary outcome. Which statement is most accurate?

Accepted Answer

If the null hypothesis were true, results this extreme would occur 3% of the time by chance

Answer

A p-value is the probability of observing results at least as extreme as those obtained, assuming the null hypothesis is true.

Question 2

Which bias occurs when participants in a study change their behavior because they know they are being observed?

Accepted Answer

Hawthorne effect

Answer

The Hawthorne effect describes behavioral change in participants who are aware of being studied, potentially distorting results.

Question 3

Specificity in a diagnostic test is defined as the proportion of:

Accepted Answer

True negatives among all those without the disease

Answer

Specificity = TN / (TN + FP), measuring how well the test correctly identifies people who do not have the disease.

Question 4

An ecological study finds a correlation between national sugar consumption and diabetes rates. The main limitation of this finding is:

Accepted Answer

Individual-level data are not used, so ecological fallacy may apply

Answer

The ecological fallacy is the error of inferring individual-level relationships from group-level (aggregate) data.

Question 5

Which of the following study designs is most appropriate for estimating disease prevalence in a population?

Accepted Answer

Cross-sectional survey

Answer

Cross-sectional surveys measure disease status and exposures at one point in time, making them ideal for estimating prevalence.

BMAT - Assessment Practice Test