PROS:

�Quick

�Cheap

�Good for studying rare diseases or health outcome because the investigators don�t have to wait for individuals to develop the disease or health outcome of interest because they begin the study with diseased and non-diseased individuals.

CONS:

�It is difficult for investigators to determine how long it took to develop the disease or health outcome because they began with individuals that either had or did not have the disease.

�Subject to recall bias because a diseased or high risk individual may remember past events differently than healthy individuals.

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