Slope Offset Adjustment
Introduction
Reagent Load/Calibration UniCel DxC Systems Instructions For Use A13914
Page 5-32 October 2005
Slope Offset Adjustment
Introduction
The Slope Offset Adjustment option allows adjustment of the slope (m) or the
y-intercept offset (b) of the regression equation used for results calculations.
Modifications are made on a per chemistry basis. The default value for the slope is
equal to "1" and the default value for offset is equal to "0."
Slope Offset Recommendations
When slope and offset modification is desired, the slope and offset values to be used
must be experimentally derived from statistically significant patient correlation
studies. It is recommended that patient samples are run over a period of several days
by both methods, using controls to monitor accuracy. A good range of data should be
achieved by analyzing below normal, normal, and above normal samples. Patient
sample data (only) should be used for linear regression analysis with Synchron values
as y values and other method values as x values. A minimum of 40 patient samples is
recommended. From this analysis, the regression equation in the following form is
obtained:
NOTICE
Adjusting the slope and offset for a chemistry may result in a mismatch of
normal range values previously established.
y = mx+b
where:
y = Synchron value
x = other method value
m = slope of regression line
b = y-intercept of regression line (offset)
To Next Page
Loading...
Need help?
General
