The type of control problem that can occur when volunteers are compared with nonvolunteers is
A) history.
B) pretesting.
C) regression.
D) posttesting.
E) selection-maturation interaction.

Question

Quizplus · Accepted Answer

This is known as the selection-maturation interaction problem which can occur when comparing volunteers with nonvolunteers. This may arise because people who choose to volunteer may not be representative of the general population being studied and therefore may differ in important ways. Additionally, the passage of time can result in changes in both groups, which may not be equivalent, leading to a selection-maturation interaction.

The Type of Control Problem That Can Occur When Volunteers