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Clinical Trial Design

Clinical trials follow a well-established system. This system is designed to ensure both the well being of the volunteer and the scientific validity of the study. Clinical trial design is standardized and human testing occurs only after extensive laboratory study and animal tests have been completed and evaluated. Human testing is broken down into four separate phases:

Phase I: Phase I trials identify the safety and/or side effects of the experimental treatment. The study group for Phase I trials is small; usually as few as 20 to 80 healthy volunteers participate.
Phase II: Phase II clinical trials continue the work done in Phase I. Larger groups of participants are recruited to see if the experimental treatment is effective and to further evaluate its safety.
Phase III: When Phase III clinical trials start, the need for clinical trial recruiting becomes essential, as thousands of participants may take part in the study. Usually, one group receives the experimental treatment and another group receives a placebo or the standard treatment for the condition. The two outcomes are compared for safety and effectiveness. This phase may take several years.
Phase IV: Phase IV is the last phase of clinical trial design, and the only phase to take place after the Food and Drug Administration (FDA) approves the treatment. During Phase IV the long-term effectiveness and/or additional uses of the drug may be studied. By necessity, this stage lasts several years.

Placebos and Clinical Trials
Clinical trials compare experimental treatments with established treatments. Occasionally, volunteers may be given a placebo (medication without the active ingredient of the drug being studied) rather than the experimental drug. In other cases where a control group is needed, participants are given the best current treatment instead of a placebo, particularly where the participants have life-threatening illnesses such as cancer.

Randomization
Randomization is an essential part of clinical trial design. In order to ensure that the trials are as fair as possible, volunteers who meet a trial's criteria are chosen at random for membership in the experimental group-the participants who receive the new treatment-or the control group-the participants who receive the placebo or standard treatment. Note that your physician and the researchers administering the study have no knowledge of your group placement during the trial.

Clinical Trial Recruiting
What can you expect from the clinical trial recruiting process? After you express your interest in a clinical trial, you will be contacted by phone, email or mail. You will be asked for specific information about your medical history and condition as part of a preliminary screening process to determine if your circumstances meet the trial's needs. If you do fit the profile needed for the study, your name will be added to the list of possible participants. You'll be notified if you've been chosen to participate and told when to meet with the medical personnel running the trial for your first visit.