In a study on the effects of caffeine on memory, Dr. Levine asked participants to drink a bottle of unflavored water containing 100, 50, or 0 milligrams of caffeine. Neither Dr. Levine nor the study participants knew whether the water contained caffeine or not. This is an example of a _____ study.
A)correlational
B)case
C)single-blind
D)double-blind

Question

Quizplus · Accepted Answer

This is a double-blind study because both the participants and the experimenter (Dr. Levine) are unaware of whether the water contains caffeine or not, which helps to reduce bias and increase the validity of the results.

In a Study on the Effects of Caffeine on Memory