Clinical trials are often considered as the ways to test a new drug or medicine. However, they can also be used to diagnose or prevent a disease from occurrence. The various types of clinical trials currently in use are,

Prevention trials:

1. The substances or the ways that could cause a particular disease are seen in these prevention trials.
2. For example: the lung cancer is caused by excessive smoking and smoking long time. While performing prevention trials, this is identified.

Screening trials:

1. The stage of diagnosis of a disease is done in screening trial.
2. It is performed to see the stages of development of the disease and the stage when it can be cured.

Diagnostic trials:

1. This is performed to perfectly identify the presence of the disease in the person.
2. This trial more accurately determines the stage of the disease.

Treatment trials:

1. Here the effectiveness of drugs, surgery, or radiations that can cure the disease is tested.
2. For example: cancer in its earliest stages can be cured by radiations. The Treatment trials involve using radiations; medications etc and try to cure the disease.

Support care trials:

1. They are also known as the quality of life trials.
2. They are done to study the ability of the drug to suppress the behavior or symptom of a disease.
3. Sometimes a procedure can also suppress the symptom of a disease. All these are studied in this trial.

Phases of clinical Trials

There are three phases of trials. They are phase 1, phase 2 and phase 3 trials. Each is performed at various levels and has various goals.