The most obvious advantage of a clinical trial is that you have access to a new treatment that you wouldn’t have otherwise. People are likely to go through regular testing which is in most cases very beneficial to the patient. The risk always involves that the treatment may not work and instead have side effects. Sometimes the side effects can be even worse than the current treatment. Patients usually may not like the uncertainty of not knowing whether you are taking an active new drug, the standard treatment, or a placebo. The biggest factor is that insurance company may not cover the costs of this new treatment. This very reason can be discouraging for most people for taking a part in clinical trials.