MCCQE Population Health and Epidemiology 3

Question 1

A researcher finds an odds ratio of 2.5 (95% CI: 0.9–6.8) for the association between a dietary factor and colon cancer. What is the correct interpretation?

Accepted Answer

The result is not statistically significant at the 0.05 level

Answer

Because the 95% CI crosses 1.0, the result is not statistically significant at α = 0.05.

Question 2

Which epidemiological study design provides the strongest evidence for causality?

Accepted Answer

Randomized controlled trial

Answer

Randomized controlled trials minimize confounding through randomization, providing the strongest causal evidence.

Question 3

In Bradford Hill's criteria, which criterion addresses the plausibility of the cause-effect relationship based on current biological knowledge?

Accepted Answer

Biological plausibility

Answer

Biological plausibility requires that the association makes sense given existing biological and medical knowledge.

Question 4

A screening test for colorectal cancer is applied to 10,000 people; 200 test positive, 50 have true disease (all test positive), and 150 are false positives. What is the specificity?

Accepted Answer

98.4%

Answer

Specificity = TN / (TN + FP) = 9,800 / (9,800 + 150) = 9,800/9,950 ≈ 98.5%.

Question 5

Which of the following best describes a systematic review?

Accepted Answer

A comprehensive synthesis of all relevant studies on a topic using explicit methods

Answer

Systematic reviews use pre-specified, reproducible search and selection criteria to synthesize evidence from multiple studies.

(MCCQE) Medical Council of Canada Qualifying Examination Practice Test

(MCCQE) Medical Council of Canada Qualifying Examination Practice Test

MCCQE Population Health and Epidemiology 3