Dr. Foster is studying the effectiveness of a new memory-boosting diet supplement. He posts an ad for subjects at two local colleges. He assigns 55 students from college A to the treatment group (daily doses of the diet supplement) and 60 students from college B (no supplement) to the control group. After 6 months of the study, Dr. Foster gives all of the students in each group a memory test. The treatment group scores an average of 20 points higher than the control group (a significant difference). Based on these findings, Dr. Foster declares that the memory-boosting supplement helps increase a person's memory. What would improve the design of the Dr. Foster's study?

Question

A) Make the number of students in both groups the same.
B) Randomly assign students to one of the two conditions (treatment or control).
C) Administer the supplement for a longer period of time.
D) Give the control group half the daily dosage of the diet supplement that the treatment group receives.
E) Deprive the control group of sleep to see if that also affects memory recall.

Answer 1

B) Randomly assign students to one of the two conditions (treatment or control).