Which Situation Represents a Threat to Internal Validity in an Experimental

question 32

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 participants 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:

Sheldon Cohen

A psychologist known for his research on the effects of stress, social support, and the common cold on human health and well-being.

Inadequate

Lacking the quality or quantity required; insufficient for a purpose.

Biomedical

Pertaining to the application of the natural sciences, especially biology and physiology, to clinical medicine.

Educational Level

The highest degree or level of school completed by an individual, often affecting their job opportunities and social status.