Chapter 9

Question 1

Which study provides a snapshot of the health status of a population at one point in time?

Answer 1

Cross-sectional survey

Question 2

Cross-sectional studies are also called:

Answer 2

Prevalence studies

Question 3

Why are cross-sectional studies the most popular study approaches in the health sciences?

Answer 3

Because they allow for the rapid collection of new data

Question 4

What is the goal of a cross-sectional survey?

Answer 4

To measure the proportion of the population with a particular exposure and disease

Question 5

A cross-sectional study should be done over a ____(long/short) period of time based on a representative sample of a population.

Answer 5

Short

Question 6

Cross-sectional surveys are used to:

Answer 6

1) Describe communities
2) Assess population needs
3) Support program planning
4) Monitor and evaluate programs
5) Establish baseline data prior to the initiation of longitudinal studies

Question 7

What is epidemiology?

Answer 7

The study of the distribution and determinants of health of populations

Question 8

Explain a cross-sectional study

Answer 8

The researcher asks a few hundred people to complete a short questionnaire, and then the data is analyzed.

Question 9

What is one important requirement for the participants in a cross-sectional survey?

Answer 9

The participants must be reasonably representative of some larger population

Question 10

What does representativeness mean?

Answer 10

The sample population must be as diverse as the source population

Question 11

When do we do cross-sectional surveys?

Answer 11

1) The time is limited

2) The budget is small

Question 12

What statistical measure do we use for cross-sectional surveys?

Answer 12

Prevalence

Question 13

What is a KAP survey?

Answer 13

A commonly used type of cross-sectional study that asks participants about their Knowledge, Attitudes, and Practices.

Question 14

KAP surveys can be particularly helpful for:

Answer 14

Identifying gaps between what people know and how they act on that knowledge.

Question 15

Give an example on KAP survey.

Answer 15

The adults in the survey might demonstrate high knowledge about the benefits of exercise on cardiovascular health but at the same time indicate that they rarely exercise because a variety of perceived barriers prevent them from being as physically active as they know they ought to be for maximum fitness.

Question 16

What does a repeated cross-sectional study do?

Answer 16

Re-samples and re-surveys representatives from the same source population at two or more different time points.

Question 17

Which method is used for large studies conducted by the CDC?

Answer 17

Repeated cross-sectional surveys

Question 18

Give three examples of repeated cross-sectional surveys

Answer 18

1) Behavioral Risk Factor Surveillance System (BRFSS)
2) National Health and Nutrition Examination Survey (NHANES)
3) U.S. National Health Interview Survey (NHIS)

Question 19

True or false:

A repeated cross-sectional study design tracks the same individuals forward in time.

Answer 19

False; A new set of participants is sampled from the source population each time a survey is conducted.

Question 20

Repeated cross-sectional surveys can reveal trends in:

Answer 20

Population-level metrics over time (NOT individual level changes)

Question 21

Which study is used to study individual participants over a long period of time?

Answer 21

Longitudinal cohort study.

Question 22

Cross-sectional surveys measure the prevalence of various:

Answer 22

1) Exposure histories
2) Disease states
3) Demographic characteristics
In one well-defined population at one point in time (or short period of time)

Question 23

What is the most common way to report results for a cross-sectional survey?

Answer 23

By reporting the prevalence rate

Question 24

What is the prevalence rate?

Answer 24

The percentage of the population with a given trait at the time of the survey.

Question 25

What other ways can you report the results for a cross-sectional survey?

Answer 25

By comparative measures, such as prevalence rate ratios.

Question 26

What are prevalence rate ratios?

Answer 26

They compare the prevalence of a characteristic in two population subgroups by taking a ratio of their prevalence rates.

Question 27

Can cross-sectional surveys assess causality? Why or why not?

Answer 27

No they cannot, because a cross-sectional survey has no time dimension. We can say that an exposure can be “associated” or “related to a disease but we cannot show that an exposure caused a disease.