Medical reseach conducted to investigate various aspects of disease such as how many people are at risk, how do people get the disease, and what treatment can help or cure the disease. It may show a treatment that is new or compare a current therapy with a treatment that the study’s researchers believe is more effective.
Clinical trials are set up in the following steps called phases:
Phase I
A small trial to test a new treatment in a small number of patients to determine how the treatment can be given and to monitor how the patient responds.
Phase II
A larger trial to examine how well the treatment works and look for side effects which are still largely unknown.
Phase III
If the treatment in phase II shows promise of improvement and safety over current therapy, it can move to phase III. This trial compares the results of people taking the new treatment with results of people taking current therapies. Patients are divided into treatment groups. One group receives the new treatment and the other receives the current treatment. When subjects do not know which group they are in, this study is called a blinded trial. If neither the subjects nor the researchers know which treatment is given, it is called a double blinded trial.