research studies that use human volunteers, usually to test new drugs or other treatments to compare current, standard treatments with others that may be better. They may also test new ways to diagnose or prevent a disease. Before a new treatment or test is used on people, it is studied in the lab. If lab studies suggest it will work, the next step is to test it in patients. There are 3 main questions the researchers want to answer.
Does this treatment or test work better than what we use now?
What side effects does it cause?
Do the benefits outweigh the risks?