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:

OSHA Guidelines

Regulations and recommendations provided by the Occupational Safety and Health Administration aimed at ensuring a safe and healthy workplace.

Invasive Procedure

An invasive procedure involves entering the body or breaking the skin barrier through methods such as surgery, injections, or insertion of medical instruments.

High-Level Disinfection

The process of eliminating all microorganisms, except for a small number of spores, from instruments or surfaces using chemical agents.

Autoclave

A pressure chamber used to sterilize equipment and supplies by subjecting them to high-pressure saturated steam at 121 °C or more.