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The mean for a group of data points is simply the calculated average. The mean provides a laboratory's best estimate of the analyte's "true" value for a specific level of control. The mean a predetermined number of standard deviations represents the error expected in a test when the analytical system is stable. Use the following formula to calculate the mean:

See Also

Useful Statistics

Standard Deviation (SD)

Calculating a Control Mean and Range

Standard Deviation Index (SDI)


Coefficient of Variation (CV)

Determining an Acceptable CV

Coefficient of Variation Ratio (CVR)

Total Error (TE) and Total Allowable Error (TEa)