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Questions About Cancer? 1-800-4-CANCER

NCI Dictionary of Cancer Terms

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historical control subject  listen  (hih-STOR-ih-kul kun-TROLE SUB-jekt)

  An individual treated in the past and used in a comparison group when researchers analyze the results of a clinical study that had no control group. The use of a control, or comparison, group helps researchers determine the effects of a new treatment more accurately.