What is a clinical trial?
A clinical trial is a type of medical research study that helps answer important questions about human health, such as how illnesses and disease are identified, treated and managed. In a clinical trial, researchers test an intervention, like a drug, medical device, procedure or a change in behavior to learn if it is safe and effective in people. Clinical trials depend on volunteers (participants) to answer these questions and improve health.
There are different types of clinical studies; they do not always test medicines. Some look at the long-term effects of treatment or the impact of diet, nutrition and exercise on illness or disease. Some need volunteers with specific illnesses and some need healthy volunteers. Some examine the effects of a new drug, vaccine or treatment and others monitor large populations in normal settings to compare changes over time.