A clinical trial is a research study conducted to evaluate the safety and effectiveness of new medical treatments, drugs, or devices. These trials involve human participants and are designed to answer specific health questions. They follow a structured protocol and are often divided into phases, each with distinct goals and criteria for participation. Participants in clinical trials may receive the experimental treatment, a standard treatment, or a placebo. The results help researchers determine how well the treatment works and identify any potential side effects. Regulatory agencies, such as the U.S. Food and Drug Administration (FDA), oversee these trials to ensure ethical standards and participant safety.