An experiment in which neither the subjects nor the individuals running the study know which subjects are in the control group and which are in the experimental group until after the results are tallied is called a study.

Double Blind Study or Blinded Experiment

Explanation:

A Double Blind Study or Blinded Experiment, is a study which neither the members nor the experimenters realize who is getting a specific treatment.

It successfully eliminates biased and one-sided results.

Often used to effectively eliminate bias from individuals that might experience a sham treatment or effect on the placebo.

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