Cross Sectional Studies

Question 1

Cross Sectional Studies

Answer 1

Simultaneous collection of info regarding exposure and outcome

Question 2

3 Benefits of CSS

Answer 2

Good to generate (not test) hypotheses
Good to measure prevalence
Good to ID associations

Question 3

3 Limitations of CSS

Answer 3

Exposure/disease measured at same time so can’t determine temporality
Survival Bias
Single measure of exposure - most change over time

Question 4

Ecological Study (& major major point)

Answer 4

Variables measured at group level instead of individual. CAN’T APPLY FINDINGS TO INDIVIDUALS from this data (ecological fallacy)

Question 5

3 Types of Ecological Variables

Answer 5

Aggregate Variables - group means derived from individuals (like % of smokers in country)
Environmental Variables - like air pollution
Global Variables - group attribute like type of healthcare system