Case-control studies

Definition

Case-control studies are observational studies that compare individuals with a disease (cases) to those without the disease (controls) to identify possible causes or risk factors. They are often used in epidemiology to study rare diseases or outcomes.

5 Must Know Facts For Your Next Test

1. Case-control studies are retrospective, meaning they look back in time to assess exposure status.
2. They are useful for studying rare diseases because they start with known cases of the disease.
3. These studies can help identify associations but cannot definitively establish causation due to potential biases.
4. Selection of controls is crucial; controls should be similar to cases except for the presence of the disease.
5. Data collection often relies on medical records, interviews, or questionnaires.

Review Questions

• What type of study design is a case-control study?
• Why are case-control studies particularly useful for studying rare diseases?
• How do researchers select controls in a case-control study?

Related terms

Cohort Study: An observational study where subjects are followed over time from exposure to outcome.

Cross-Sectional Study: A study that analyzes data from a population at a single point in time.

Odds Ratio:

A measure used in case-control studies to quantify the strength of association between exposure and outcome.