In drug-treatment studies, double-blind procedures minimize outcome differences between experimental and control conditions that could be attributed to

a. replication.
b. operational definitions.
c. random sampling.
d. placebo effects.

d. placebo effects

Explanation:

What Is the Placebo Effect?

- The placebo effect is a phenomenon in which a person may start to feel like an inactive substance has actual healed them or has given them some benefits.

A placebo is only an inactive ,non medical substance which has no medical effect on a person and ig could be sterile water , saline solution or a sugar pill.

People may experience real changes through a fake treatment because of their expectations of they expect it to work they would start to actual feel it work.

It occurs mostly when a person doesn't know that what they are receiving isn't real medicine

A double-blind study refers to when both experimenters and participants doesn't know which is drug and which isn't

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