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Common Statistic of The Clinical Biochemistry
Inaccuracy = Bias = (Laboratory Value - True Value)
Inaccuracy % = Bias % = [(Laboratory Value - True Value) x 100] / True Value
True Value may be “EQAS Mean of Comparison”.
Imprecision = CV% = (IQC-SD x 100 / IQC-Mean)
Total Error % (TE % ) = (Bias % + 2CV%)
Total Error (TE) = (Bias + 2SD)
Standard Deviation Index = SDI = (IQC Value - IQC Mean) /IQC-SD
Z Score = (EQAS Value - EQAC Mean of Comparison) /EQAS-SDPA