Which Situation Represents a Threat to Internal Validity in an Experimental

question 27

Multiple Choice

Which situation represents a threat to internal validity in an experimental study measuring the effect of a videotape of discharge instructions for patients who underwent coronary artery bypass graft (CABG) surgery?

• A) Both men and women undergoing CABG surgery were included as subjects in the study.
• B) Two new surgeons began performing CABG surgery during the study period.
• C) Patients in the experimental group discussed aspects of the videotape with patients in the control group.
• D) Data collection for the videotape and control groups took 1 year.

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Definitions:

Expropriation

The governmental seizure of private property without the owner's consent, often with compensation.

Extraordinary Item

Extraordinary items were once classified on income statements to denote unusual or infrequent transactions that were distinct from regular business operations, but accounting standards have evolved to limit or exclude these classifications.

Extraordinary Losses

Non-recurring losses that are unusual in nature and infrequent in occurrence, significantly impacting a company's financial performance.

Tornado Damage

The destruction or loss caused by a tornado, affecting buildings, infrastructure, and communities, potentially leading to financial losses and insurance claims.