In a Study in Which a Data Point Is Gathered

question 13

Multiple Choice

In a study in which a data point is gathered more than once and the same instrument or survey is used each time, results of the study may be questioned due to which threat of internal validity?

• A)history
• B)instrumentation
• C)testing
• D)selection
• E)none of the above

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Definitions:

Donors

Individuals who provide blood, organs, tissues, or other biological materials for medical purposes.

Acid-Base Balance

The mechanism that the human body uses to maintain a stable pH level in its fluids and tissues.

Respiratory Mechanisms

The physiological processes involved in the intake of oxygen and the release of carbon dioxide from the body.

Renal Mechanisms

The processes and functions carried out by the kidneys to regulate body fluids, electrolytes, and waste product removal.