MPH Epidemiology & Biostatistics 2

Question 1

In a case-control study, which measure of association is typically calculated?

Accepted Answer

Odds ratio

Answer

Odds ratios are used in case-control studies because true incidence rates cannot be directly calculated from this design.

Question 2

What is 'selection bias' in epidemiological research?

Accepted Answer

Systematic error in how participants are recruited into a study

Answer

Selection bias occurs when study participants are systematically different from the target population due to flawed selection procedures.

Question 3

The number needed to treat (NNT) is the reciprocal of:

Accepted Answer

Absolute risk reduction

Answer

NNT = 1 / Absolute Risk Reduction, representing how many patients must be treated to prevent one additional adverse outcome.

Question 4

Which statistical test is appropriate for comparing means between two independent groups?

Accepted Answer

Independent samples t-test

Answer

The independent samples t-test compares means from two unrelated groups to determine if they differ significantly.

Question 5

Confounding in epidemiology refers to:

Accepted Answer

A third variable that is associated with both exposure and outcome

Answer

A confounder is a variable related to both the exposure and the outcome that can distort the true association between them.

MPH - Master of Public Health Practice Test