Clinical trials are medical and scientific tests designed to gather data on new drugs and medical treatments using human volunteers. Clinical trials study many different diseases. They look at ways to prevent disease, new ways to diagnose disease and potential new treatments. As an example a clinical trial may study anything from a new lotion to treat acne to a long-term pill to help prevent cancer. Government agencies, private organizations and pharmaceutical companies sponsor clinical trials. The goal is to find a better treatment than the one that is currently available.