There are four different types of cancer clinical trials, which include:
Treatment trials, which test new drugs, medical procedures, or combinations of treatments.
Prevention trials, which look for better ways to prevent diseases by either doing something (called action studies) like making lifestyle changes, or taking something (called agent studies) such as medicines, vitamins, or minerals.
Screening trials, which look for new ways to test for the presence of a disease or health condition early, when it may be more easily treated.
Quality of life trials, which explore ways to improve comfort and quality of life for cancer patients.