Controls Are Needed in a Case‐control Study Because

question 4

Multiple Choice

Controls are needed in a case‐control study because:

• A)They may be followed to determine if they have the disease in question
• B)They increase the sample size so that statistical significance can be achieved
• C)They provide a comparable estimate of the frequency of exposure in the absence of disease
• D)They are matched to cases on suspected risk factors

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Definitions:

Crenated

Describes a process where cells, typically red blood cells, shrink due to osmosis, resulting in a notched or scalloped appearance.

Phagocytized

The process by which cells engulf and digest solid particles or other cells.

Normal

Referring to a condition or parameter that falls within the expected range for a given population or system.

Free Radicals

Highly reactive molecules with unpaired electrons that can cause cellular damage but also play roles in cell signaling.