2 Epidemiology Basics Online Quiz Questions

On a survey date, 40 of 800 people in a population have asthma. What is the point prevalence of asthma?

True or false: If a study finds that groups with higher average exposure also have higher disease rates, it has established that individuals with the exposure are more likely to have the disease.

Researchers classify participants by whether they have a workplace exposure and then follow both groups to compare new disease cases. Which study design best describes this approach?

Over the same period, the risk is $18\%$ in an exposed group and $12\%$ in an unexposed group. What is the risk difference in percentage points? Enter a numeric value; the answer is displayed with a % suffix.

True or false: Finding an association between an exposure and an outcome is, by itself, proof that the exposure caused the outcome.

During the same period, 20 of 200 exposed people and 10 of 200 unexposed people develop a condition. What is the risk ratio comparing the exposed group with the unexposed group?

Which statements describe a case-control study? Select all correct answers.

A health department estimates the proportion of residents who had asthma at any time during the past year, including both new and pre-existing cases. What measure is it estimating?

An observational study reports an association between an exposure and a health outcome. Which steps support a careful interpretation? Select all correct answers.

A health team is considering whether results from a study conducted in one population and setting apply to a different population. Explain what features of the study and its context the team should compare, and why those features matter.

True or false: Random assignment can help balance other causes of an outcome between groups, but it does not ensure that a trial's results apply to every population.

Two studies estimate the same association, but one has a much wider confidence interval. What does the wider interval indicate?

A clinic wants to estimate how widespread a chronic condition is among its patients on a particular survey date. Which measure is most appropriate?

Researchers measure participants’ current exposure and health status in the same survey, with no follow-up. Which study design best describes this approach?

During one year, 12 of 200 initially disease-free people develop an illness. What is the one-year incidence proportion?

Researchers select participants with and without a rare outcome, then compare their prior exposures. Which measure of association would they generally use?

During the same period, 20 of 200 exposed people and 10 of 200 unexposed people develop a condition. What is the risk difference? Give the value in percentage points.

A study's exposure data are systematically misrecorded, distorting comparisons between groups. What broad epidemiologic error category does this illustrate?