This problem occurs when the groups become different after the experiment begins because more participants drop out of one of the groups than out of the other(s)for various reasons.
A)selection bias
B)maturation
C)regression
D)differential attrition

Question

Quizplus · Accepted Answer

Differential attrition refers to the phenomenon of having different rates of dropouts among different groups. This can lead to biased results as the groups may no longer be comparable due to the loss of participants.

This Problem Occurs When the Groups Become Different After the Experiment