MEAN (CDC). The measure of central location commonly called the average. It is calculated by adding together all the individual values in a group of measurements and dividing by the number of values in the group.

For “mean elimination half-life”, time the average person shall metabolize (reduce) amount of the substance by 1/2. For example, after 36 hours theoretically the average person shall have only 5.0 mg valium remaining in system, 36 hors later 2.5 mg remains, etc., etc., . . . Another way to put it . . . the time it takes for the body to eliminate or breakdown half of a dose of a pharmacologic agent.

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