Randomized controlled trials (RCTs) are a type of scientific study in which participants are randomly assigned to either a treatment group or a control group. The treatment group receives the intervention being tested, while the control group does not receive the intervention or may receive a placebo or standard treatment. RCTs are considered the gold standard in research because they help minimize bias and allow researchers to accurately assess the effectiveness of a particular intervention. This method is commonly used in medicine, psychology, and social sciences to evaluate the efficacy of new treatments, therapies, and interventions.