Bio-Rad iQ™5 Optical System Software, Version 2.1 - Manual (Page 99)

Section 6 Data Analysis Module
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Corrected Values Calculations
The efficiency value (E) used in gene expression calculations has an associated error. If a
standard curve was generated as part of the real-time PCR assay, this error can be calculated
and used to adjust the error associated with the following standard deviation values:
•
Rel Quant SD
•
Unscaled Expression SD
•
Expression SD
Corrected Values for all gene expression results are displayed on the Data Table spreadsheet
when Show Details is selected (Figure 6.48). When Show Details is active, three new columns
appear in the Data Table spreadsheet. The new columns display the error correction propagated
from the standard curve data for:
•
Relative Quantitation Standard Deviation
•
Unscaled Expression Standard Deviation
•
Expression Standard Deviation
The new columns are named:
•
Corrected Rel Quant SD
•
Corrected Unscaled Expression SD
•
Corrected Expression SD
Fig. 6.48. The Gene Expression analysis Data Table – Show Details view.
A difference between corrected and non-corrected values will only be seen if a standard curve
was created as part of the real-time PCR assay. The equations used in determining the error
propagation are the Standard Error, Standard Error for Normalized Expression, and the Standard
Error for the Normalized Gene of Interest (GOI).
The equation for Standard Error is shown below:
n
SD
SE =