In a study investigating the effect of type of operating room mattress and surgical position on tissue interface pressures,the researchers used healthy young adult subjects.Which component of research design is most affected by this choice?
A) Internal validity
B) Mortality
C) Instrumentation
D) External validity

Question

Quizplus · Accepted Answer

Correct D: Subject selection affects external validity because most surgical patients are not healthy young adults.
Incorrect A: Internal validity would not be affected because selection bias was not an issue.
Incorrect B: Attrition of subjects would not be influenced by healthy young adult status.
Incorrect C: Instrumentation would likely be unaffected by using healthy adults.

In a Study Investigating the Effect of Type of Operating