Even if you randomly assign subjects to groups, which of the following may result in you ending up with groups that are not comparable?
A) attrition
B) contamination
C) placebo effect
D) maturation

Question

Quizplus · Accepted Answer

Attrition can result in groups that are not comparable because it can lead to differences in the characteristics of the participants in the different groups. For example, if participants in one group are more likely to drop out of the study than participants in another group, this could lead to differences in the average age, education level, or other characteristics of the participants in the two groups.

Even If You Randomly Assign Subjects to Groups, Which of the Following