How Do Case-Control and Cohort Designs Differ

question 3

Multiple Choice

How do case-control and cohort designs differ?

• A) In case-control, the groups are studied prospectively, but in cohort designs, the groups are studied retrospectively
• B) In case-control, only one group is studied, but in cohort designs, more than one group is studied
• C) In case-control, the groups are selected on the basis of an outcome that has already occurred, but in cohort designs, the groups are selected before the outcome has occurred
• D) In case-control, the groups are selected before the outcome has occurred, but in cohort designs, the groups are selected on the basis of an outcome that has already occurred

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Definitions:

Lymphangitis

Inflammation of the lymphatic channels, typically resulting from a bacterial infection, and leading to red, painful streaks under the skin.

Cellulitis

A bacterial infection of the skin and tissues beneath the skin, leading to redness, pain, and swelling.

Macule Skin Lesion

A flat, distinct, colored area of skin less than 1 cm wide without any change in the texture or thickness of the skin.

Nonpalpable

Unable to be felt by touch, often referring to abnormalities within the body that cannot be detected through physical examination.