Volunteers for a research study could introduce bias because
A) they are less likely to show change than subjects who are required to participate.
B) they may be different from nonvolunteers on important variables.
C) they are more subject to the Hawthorne effect than nonvolunteers.
D) Al of these are true.

Question

Quizplus · Accepted Answer

Volunteers may be different from nonvolunteers on important variables, which can introduce bias into the study. They may be more motivated or have a greater interest in the topic being studied, which could affect the results. The other options are not necessarily true in all cases and do not specifically address the potential bias introduced by the volunteers themselves.

Volunteers for a Research Study Could Introduce Bias Because