Question

In double-blind studies neither the test subject or the researcher knows who was given the drug and who was given the control. Why are these studies effective for testing a drug that may elevate mood and relieve feelings of depression?
Since there are two symptoms that are affected, a double-blind study is required.
Double-blind studies are ways to ensure that only the researcher can figure out who is getting the effective drug.
Double-blind studies are the most economical way to gather results from testing on humans.
The patients and researchers are not given this information so they cann