Clinical studies refer to research investigations that involve human participants. These studies are designed to evaluate the safety and effectiveness of medications, treatments or interventions, and may also be used to gather information about the natural history of a disease or condition. Clinical trials typically follow a specific protocol, which outlines the study design, objectives, eligibility criteria for participants, and the procedures that will be followed during the trial. Participants in clinical studies are usually volunteers who receive compensation for their time and effort. The results of these studies can help to improve medical care and contribute to advances in scientific knowledge.