OpenLab - Compound_CalibAmount in table but displayed for sample not for calibration standard

Hello,

You cannot use the calibration table in calculations unless you have a cal std in the result set. You will need to use a compound custom field to enter the calibration values for the check injections in this case. You could use a CC constants file as well if the standard values do not change often. 

Marty Adams

Thanks. I will try CC. Will it work with built-in report as custom field or I need to create new report template from scratch?

Tom

On your other question from the most recent comment, you can access CC file variables from the report, but they likely won't do it for you. You won't have to start from scratch on a brand new report, but just modify an existing report to include those constants where you want and save it as a different report to preserve the default. If you want to show them inline to a table, you will likely have to create a custom calculation that links the concentration you want to a new variable keyed by sample_ID and have some criteria to limit this to only the control sample. Then you call that variable in a specific column of the table. If you aren't familiar with the reports, this may be a bit difficult, but once you know the basics it won't be too hard.

I'm unsure if you will be able to quantify concentrations of samples automatically without any calibration standards in the sequence, but you will certainly be able to access the concentrations of the standards with the CC file. You can try pulling both the calibration data and the sample data using one report if the CC file doesn't give you what you want. It is pretty quick and easy to do. If it wont quantify sample concentrations, you can either merge them into one data set, which will allow it to quantify for sure or you can set up the calculations manually in the report.

I understand why you wouldn't want to make calibration standards every time, but determining if a whole curve is still valid by testing one point may not always give the right answer. For methods that have gone through a whole validation proving linearity with an insignificant y-intercept, it is generally acceptable to switch to a single point calibration, which is about the same as you are talking about, but with a few injections to gather statistical variability. However, the difference here is that the calibration always depends on the calibration in the most recent control samples. If there is drift, the new calibration data aligns with it. Of course, you can calculate however you want. I'm just trying to protect your results from regulatory ridicule. There are multiple issues that can occur over the lifespan of an instrument that can change what the correct calibration curve is and checking one point of the curve may not always tell you when they are happening. Always cover your rear or it may just come back to bite you.

Hello,

I think there are other posts where I go over this in more detail. If you want to do a recovery or check calculation for more than one compound and it is not a reinjection of a standard level or the standards are not in the results set, the easiest way is a compound custom field. You setup a compound custom field in the CDS project and then fill in the values for each compound when running the sequence or in DA. You will need to enter the values for all injections where you are doing the calculations. You can then add a column to your tables where you calculate the error or recovery values you want. 

Marty Adams

=Val(Compound_Amount / CFE((Compound_CustomFields),"QC Conc") * 100)