MPH Epidemiology & Biostatistics 3

Question 1

Sensitivity of a diagnostic test refers to:

Accepted Answer

The ability to correctly identify those with the disease

Answer

Sensitivity is the proportion of true positives correctly identified — a highly sensitive test misses few cases.

Question 2

Which type of bias occurs when disease status influences recall of past exposures?

Accepted Answer

Recall bias

Answer

Recall bias occurs when cases remember past exposures differently than controls, often due to their illness prompting more reflection.

Question 3

What does 'attributable risk percent' measure?

Accepted Answer

The proportion of disease in the exposed that is due to the exposure

Answer

Attributable risk percent (etiologic fraction) estimates the proportion of disease in exposed individuals that can be attributed to the exposure.

Question 4

A Kaplan-Meier curve is used to:

Accepted Answer

Display survival or event-free probabilities over time

Answer

Kaplan-Meier curves graphically display the probability of surviving (or remaining event-free) over a study period.

Question 5

Effect modification (interaction) in epidemiology means:

Accepted Answer

The effect of an exposure on an outcome differs across strata of a third variable

Answer

Effect modification occurs when the magnitude or direction of an association varies across levels of another variable, indicating a true biological or social interaction.

MPH - Master of Public Health Practice Test

MPH - Master of Public Health Practice Test

MPH Epidemiology & Biostatistics 3