How many participants would be needed for a repeated-measures experiment comparing four different treatment conditions,which investigated 20 participants in each treatment?
A) 20
B) 5
C) 80
D) Cannot answer without more information

Question

Quizplus · Accepted Answer

In a repeated-measures design, the same participants are used across all treatment conditions, so if there are 20 participants in each treatment and all treatments involve the same participants, only 20 participants are needed in total.

How Many Participants Would Be Needed for a Repeated-Measures Experiment