What type of trial is indicated when neither the participants nor researchers know who is receiving treatment?

A double-blind study is characterized by both participants and researchers being unaware of who is receiving the treatment and who is receiving a placebo or a different intervention. This design is crucial for minimizing bias in clinical trials, as it helps to ensure that the outcomes are not influenced by the expectations or behaviors of either the participants or the researchers. In such studies, the data collected is considered more reliable because any psychological effects—such as the placebo effect—are less likely to interfere with the results.

The double-blind setup is often employed in pharmaceutical research to objectively evaluate the effects of drugs while controlling for confounding factors related to the participants' or researchers' perceptions. By keeping both parties in the dark regarding treatment assignment, it enhances the validity of the trial's findings and supports the integrity of the scientific process.