Français | Español BASELINE: 1. Information gathered at the beginning of a study from which variations found in the study are measured. 2. A known value or quantity with which an unknown is compared when measured or assessed. 3. The initial time point in a clinical trial, just before a participant starts to receive the experimental treatment which is being tested. At this reference point, measurable values such as CD4 count are recorded. Safety and efficacy of a drug are often determined by monitoring changes from the baseline values. DOUBLE-BLIND STUDY: A clinical trial design in which neither the participating individuals nor the study staff knows which participants are receiving the experimental drug and which are receiving a placebo (or another therapy). Double-blind trials are thought to produce objective results, since the expectations of the doctor and the participant about the experimental drug do not affect the outcome; also called double-masked study. EXEMESTANE: Exemestane belongs to a class of drugs called aromatase inhibitors. Aromatase inhibitors prevent the conversion of androgens to estrogen, which is the primary source of estrogen production in postmenopausal women. Estrogen plays a key role in the development and growth of most types of breast cancer and inhibition of estrogen may prevent breast cancer in many women. Exemestane is FDA and Health Canada approved, is marketed as AROMASIN™ and manufactured by Pfizer, Inc. It is currently used for the treatment of advanced breast cancer in postmenopausal women whose disease has progressed following tamoxifen therapy. FOOD AND DRUG ADMINISTRATION (FDA): The U.S. Department of Health and Human Services agency responsible for ensuring the safety and effectiveness of all drugs, biologics, vaccines, and medical devices, including those used in the diagnosis, treatment, and prevention of HIV infection, AIDS, and AIDS-related opportunistic infections. The FDA also works with the blood banking industry to safeguard the nation's blood supply. Internet address: http://www.fda.gov/. GAIL SCORE: Health care providers use an objective measure, called the Gail score, to assess a woman's risk for breast cancer. A woman's physician can help calculate a Gail score. The score is derived after a woman answers questions such as age (the older the woman, the higher the risk of breast cancer), whether she has had any children and starting at what age, and whether she has any "first degree" family members, such as mother, sister or a daughter who have the disease. INCLUSION/EXCLUSION CRITERIA: The medical or social standards determining whether a person may or may not be allowed to enter a clinical trial. These criteria are based on such factors as age, gender, the type and stage of a disease, previous treatment history, and other medical conditions. It is important to note that inclusion and exclusion criteria are not used to reject people personally, but rather to identify appropriate participants and keep them safe. PLACEBO: A placebo is an inactive pill, liquid, or powder that has no treatment value. In clinical trials, experimental treatments are often compared with placebos to assess the treatment's effectiveness. In some studies, the participants in the control group will receive a placebo instead of an active drug or treatment. No sick participant receives a placebo if there is a known beneficial treatment. PREVENTION TRIALS: Refers to trials to find better ways to prevent disease in people who have never had the disease or to prevent a disease from returning. These approaches may include medicines, vitamins, vaccines, minerals, or lifestyle changes. RANDOMIZED TRIAL: A study in which participants are randomly (i.e., by chance) assigned to one of two or more treatment arms of a clinical trial. Occasionally placebos are utilized. SIDE EFFECTS: Any undesired actions or effects of a drug or treatment. Negative or adverse effects may include headache, nausea, hair loss, skin irritation, or other physical problems. Experimental drugs must be evaluated for both immediate and long-term side effects. Definitions found at: http://www.cancer.ca/ http://www.cancer.org/ http://www.clinicaltrials.gov