Free Practice Quiz Question List

2 Epidemiology: Concepts and Methods Online Quiz Questions

Use this free practice quiz with 20 questions to review 2 Epidemiology: Concepts and Methods, test your knowledge, and prepare for your next test or exam.

20 questions

True or false

1 point

True or false: A descriptive study can help generate hypotheses about a health pattern, but usually cannot establish why the pattern occurred.

A
True
B
False

Written response

1 point

Twenty of 200 disease-free people develop an illness during one year. What is the one-year incidence proportion, expressed as a percentage? Enter the percentage number (for example, enter 10 for 10%).

Fill in the blank

1 point

Complete the definition: An incidence rate is the number of divided by the .

Choose one

1 point

A researcher wants to calculate the incidence proportion of a condition over a defined interval. Which denominator is appropriate?

A
Everyone living in the area at the end of the interval
B
People at risk at the start of the interval
C
Only people who developed the condition
D
All people observed, whether or not they could develop the condition

Written response

1 point

What study design groups people by exposure and follows them to compare new outcomes?

Choose all

1 point

Which of the following can complicate interpretation of an observed association? Select all that apply.

A
Chance
B
A confidence interval
C
Bias
D
Confounding
E
A larger sample size
F
Measurement or selection problems

True or false

1 point

True or false: A case–control study generally calculates the risk of developing an outcome directly from its participants.

A
True
B
False

Fill in the blank

1 point

Complete the definition: Prevalence is the proportion of a population assessed that has .

Choose one

1 point

A health outcome is rare, and researchers want to compare past exposures in people who have it with exposures in a suitable group who do not. Which design is often efficient for this purpose?

A
A cross-sectional study measuring exposure and health status at the same time
B
A cohort study grouping people by exposure and following outcomes
C
A case–control study comparing prior exposures in people with and without the outcome
D
A descriptive study summarizing cases by person, place, and time

Choose all

1 point

When translating evidence into a public health decision, which considerations should be weighed? Select all that apply.

A
How many cases might be prevented and among whom
B
Whether a statistically significant result alone proves causation
C
Feasibility of the proposed action
D
Whether relative effects alone are enough to estimate local impact
E
Potential benefits and harms
F
Available resources and community context

Written response

1 point

What interval estimate shows the range of effect estimates compatible with the data and conveys precision?

True or false

1 point

True or false: In a cohort study, a risk ratio compares the incidence proportion in exposed people with the incidence proportion in unexposed people.

A
True
B
False

Choose one

1 point

Why can a cross-sectional study have difficulty supporting a conclusion about whether an exposure caused an outcome?

A
They usually follow exposed and unexposed groups to compare new outcomes.
B
Because exposure and health status are measured at about the same time, the timing may be unclear.
C
They select participants based on outcome and compare prior exposures.
D
They assign interventions randomly when feasible and ethical.

Open ended

1 point

A study reports a statistically significant association between an exposure and a health outcome. Explain why this result alone does not establish that the exposure caused the outcome, and identify important considerations for interpreting the finding.

Choose one

1 point

A public health team studies which groups are affected by a condition, where and when cases occur, and what actions could reduce the problem. Which description best captures the team's approach?

A
It studies only the treatment of illness in individual patients.
B
It studies the distribution and determinants of health-related conditions in populations to help prevent and control health problems.
C
It studies how hospitals allocate staff and equipment.
D
It studies only the biological mechanisms of infectious diseases.

Choose one

1 point

A town of 1,000 people and a city of 100,000 people each report 20 cases of the same condition during the same period. Using these population sizes as the denominators, which place has the greater per-person burden?

A
The town has the greater per-person burden.
B
The city has the greater per-person burden.
C
The per-person burden is equal in both places.
D
The per-person burdens cannot be compared using the information provided.

Written response

1 point

At the start of a defined interval, 300 people are free of a condition and at risk of developing it. During the interval, 18 develop the condition. What is the incidence proportion for the interval? Enter the percentage value; no tolerance is needed.

Choose one

1 point

Researchers classify participants by whether they have a particular exposure, then follow both groups to compare new cases of a disease. Which study design are they using?

A
Group people by exposure and follow them to compare new outcomes.
B
Select people according to whether they have an outcome, then compare past exposures.
C
Measure exposure and health status at about the same time.
D
Summarize cases by person, place, and time without comparing exposure groups.

Choose one

1 point

A survey measures current exposure and health status at approximately the same time. Which conclusion best reflects a strength and limitation of this design?

A
It estimates incidence by following an exposed group for several years.
B
It compares prior exposure in people selected as cases and controls.
C
It assigns an intervention randomly and compares later outcomes.
D
It estimates prevalence, but may not clarify whether exposure preceded the health condition.

Choose one

1 point

Investigators enroll people with a rare disease and a suitable comparison group without it, then compare their earlier exposures. Which description best fits this approach?

A
They group participants by exposure and follow them to measure new outcomes.
B
They measure exposure and health status at the same time to estimate prevalence.
C
They select cases and controls based on outcome status, then compare prior exposures.
D
They randomly assign an intervention to estimate its effect.