One hundred volunteers who suffer from severe depression are available for a study.Fifty are selected at random and are given a new drug that is thought to be particularly effective in treating severe depression.The other 50 are given an existing drug for treating severe depression.A psychiatrist evaluates the symptoms of all volunteers after 4 weeks in order to determine if there has been substantial improvement in the severity of the depression.In which situation would this study be double blind?
A)If neither drug had any identifying marks on it
B)If all volunteers were not allowed to see the psychiatrist nor was the psychiatrist allowed to see the volunteers during the session when the psychiatrist evaluated the severity of the depression
C)If neither the volunteers nor the psychiatrist knew which treatment any person had received
D)All of the above

Question

Quizplus · Accepted Answer

Double blind studies are when neither the participants nor the researcher know who is receiving the treatment or the placebo. In this case, if neither the volunteers nor the psychiatrist knew which treatment any person had received, it would be a double blind study. The other options do not meet the criteria for a double blind study.

One Hundred Volunteers Who Suffer from Severe Depression Are Available