Hello,

I want the be able to calculate the RSD of our reference injections, but we need to do it each time with a different injection. I'm out of inspiration to get them grouped together. This is the situation:

1) at the beginning of the sequence, the reference is injected 5 times

2) after 4 sample injections the reference is repeated

3) in total this are 6 reference injections, RSD needs to be calculated on those

So far no problem, but we can build the sequence endlessly with sample injections. So if we have 8 sample injections, another reference injection is made. Then we need to calculate RSD of this reference injection with the 5 injections at the beginning, but without the reference injection made after 4 sample injection.

And so on for more sample injections. I don't know how to group every time the first 5 reference injections, with each other reference injection sepperately.

Thanks in advance,

Davy

Hello,

You will need some way to differentiate the initial 5 injections of the standard you want to group with your later injections. In this example CCF, I used the sample label field with SSS to isolate those injections. Once you have that a CCF file can be used to calculate that RSD value for each injection of the level 1 standard in your sequence with the initial standards. You can name and label the CC anything you want but the scope is peak or group and the type is double. You only need the first CC in the screenshot the second was just a test. The formula is copied below.