Active (positive) Concurrent Control
In an active control (or positive control) trial, subjects are randomly assigned to the test treatment or to an active control treatment. Such clinical trial s are usually double-blind, but this is not always possible; many oncology trials, for example, are considered difficult or impossible to blind because of different regimens, different routes of administration, and different toxicities. Active control trials can have two distinct objectives with respect to showing efficacy: (1) to show efficacy of the test treatment by showing it is as good as a known effective treatment or (2) to show efficacy by showing superiority of the test treatment to the active control. They may also be used with the primary objective of comparing the efficacy and/or safety of the two treatments. Whether the purpose of the trial is to show efficacy of the new treatment or to compare two treatments, the question of whether the trial would be capable of distinguishing effective from less effective or ineffective treatments is critical .
Read more about this topic: Standard Treatment
Famous quotes containing the words active, concurrent and/or control:
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—George Eliot [Mary Ann (or Marian)
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—Philip Dormer Stanhope, 4th Earl Chesterfield (1694–1773)
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—Ron Taffel (20th century)