Double-blind study is a scientific research method in which both the researchers and participants are unaware of who is receiving the treatment and who is receiving the placebo. This method is used to minimize bias and ensure accurate results. There are several synonyms for double-blind study, including masked study, blinded trial, randomized controlled trial, and placebo-controlled trial. These terms all refer to the same research technique of controlling for the placebo effect and reducing potential bias. The use of double-blind study has become increasingly common in clinical trials for new pharmaceuticals and medical treatments, helping to establish the safety and effectiveness of new drugs.