Epidemiology: Differences between Case – control and cohort study
- Proceeds from the outcome to cause
- Starts with cases of disease
- Tests if the suspected risk factor occurs more often in the cases than that in the controls
- Usually the first study for testing a hypothesis
- Requires fewer number of participants
- Yields the results relatively earlier
- Suitable for rare diseases
- Cannot directly estimate the relative risk hence calculates the ‘Odd’s ratio’ (OR)
- Only one outcome (disease) can be studied
- Inexpensive