ctQc: Quality Control Filter for Replicate Ct Values
Description
This function applies a quality control filter to triplicate Ct values before
combining them into a single summary Ct measure.
Current implementation can only handle three replicates.
Usage
ctQc(x)
Arguments
x
Matrix with three columns, corresponding to the triplicate Ct values.
Value
Numeric vector of Ct values combined over the three replicates according to the QC filter.
Details
Applying ctQc is an alternative to averaging the triplicate Ct values. This filter was originally developed by Yasumasa Kimura
1. For each primer, sort Ct values in ascending order so we have [ct1, ct2, ct3].
2. Take two differences
difference1 := ct2 - ct1
difference2 := ct3 - ct2
If either or both have ct 40, we don't calculate the difference and set it to region 4 in the next step.
3. Take an average according to the differences.
Here we have 2 thresholds : 0.2 and 1.0. With the thresholds, we classify the 2 differences into the below regions.
region1 : difference