Cohort studies are a type of longitudinal study—an approach that follows research participants over a period of time (often many years). Specifically, cohort studies recruit and follow participants who share a common characteristic, such as a particular occupation or demographic similarity. During tRead more
Cohort studies are a type of longitudinal study—an approach that follows research participants over a period of time (often many years). Specifically, cohort studies recruit and follow participants who share a common characteristic, such as a particular occupation or demographic similarity. During the period of follow-up, some of the cohort will be exposed to a specific risk factor or characteristic; by measuring outcomes over a period of time, it is then possible to explore the impact of this variable (eg, identifying the link between smoking and lung cancer in the British Doctors Study.) Cohort studies are, therefore, of particular value in epidemiology, helping to build an understanding of what factors increase or decrease the likelihood of developing disease.
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Case-control: 1. Proceed from effect to cause. 2. Start with the disease. 3. Test whether the suspected causes occur more frequently in those with the diseases than among those without the disease. 4.Usually the first approach to the testing of a hypothesis. 5. Involve a fewer number of subjects. 6.Read more
Case-control:
See less1. Proceed from effect to cause.
2. Start with the disease.
3. Test whether the suspected causes occur more frequently in those with the diseases than among those without the disease.
4.Usually the first approach to the testing of a hypothesis.
5. Involve a fewer number of subjects.
6. Quick result.
7. Suitable for rare diseases.
8. Only for odds ratio.
9. Can’t yield information about the diseases.
10. Temporal association is never proven.
11. Recall bias is a potential problem.
12. Relatively inexpensive.
Cohort study:
1. Proceed from cause to effect.
2. Start with people exposed to risk factors or suspected cause.
3. Test whether diseases occur more frequently than in those not similarly exposed.
4. Reserved for testing or preciously formulated hypothesis.
5. Involve a larger number of subjects.
6. Long follow-up period.
7. Not suitable for rare diseases.
8. Relative and attributive risk.
9. Can yield information about more than one disease outcome.
10. Temporal association is proven.
11. Recall bias is not an issue.
12. Expensive.