Custom field for bracketing standards (%RSD and Relative area)

I would like to know how to create the custom fields for following two parameters. 

1. % RSD area for bracketing standards (%RSD area for R0101 and R0201 for the 1st set of samples, %RSD area of R0201 and R0301 for the second set of samples, and %RSD area of R0301 and R0401 for the third set of samples).
2. Relative area of samples vs. average of bracketing standards
     Relative area of Sample 1= (area of Sample 1 / average area of R0101 and R0201) x 100 
     Relative area of Sample 2= (area of Sample 2 / average area of R0101 and R0201) x 100 
     Relative area of Sample 3= (area of Sample 3 / average area of R0201 and R0301) x 100

The sequence is shown below. 

Bracketing std 1 (R0101)
Sample 1
Sample 2 
Bracketing std 2 (R0201)
Sample 3
Sample 4
Bracketing std 3 (R0301)
Sample 5
Sample 6 
Bracketing std 4 (R0401)

Any advice will be greatly appreciated. 


  • Use the wizard to setup a sample set and choose nested bracketing.
    You don't need CFs for this. Also, life will be far easier if you use S at the start of your standard labels. We reserve R... for non-standard system suitability stuff (s/n, resolution solutions etc. that do not figure into the calibration curve).
  • Honestly, for the first part of your question, use the report to calculate this as the labels in CFs for your set up is very tricky. Set up an all peaks table in your summary by all report method and add whatever fields you want like samplename, channel etc. Right click the Area field and select Column Properties and add the &RSD summary function.

    hen in the order by tab, click Data Filtering conditions and select Sample Type = Standard and Label (this is in the "Sample" tree on the left) to be Between R0101 and R0201. Copy and paste the table and change the filter on second table to Between R0201 and R0301, same for between R0301 and R0401.

    Important, make sure to untick the "Include Duplicate Results" option on the "Table" tab of your all peaks table, otherwise any standard areas used twice will be in the list i.e. the two occurrences of R0201 etc when you only want the one area.

  • For your second part, you could create a field called Amount*100 or just put 100 in the dilution cell of your sample set for each sample, presuming you don't already have a value for this. Since area/average area of standards * Value in comp editor is usually Amount anyway.
  • Thank you both so much! I created a nested bracketing sample set and then created an all peak table to to calculate %RSD of each bracketing std set.

    One question: how can I remove the extra table with just one value? I created five tables for R0501 and R0601; however, most of the time I have only one or two sets of bracketing. For example, if my run has only one set of bracketing (R0101 and R0201), I have two all peak tables in the report; first table for the results of R0101 and R0201 and another one with just the results of R0201. Is there any way to remove the second table?

    For Empower2019, for your second comment, would you please explain a little more detail? To calculate average area of each bracketing set, do I need to create a CF for each set such as 
    (R0101,1,SAME(Area)+R0201,1,SAME(Area)) /2   ?

    I also created a CF "R0%,%,SAME,AVE(Area)"; however, it calculates average of all bracketing standard injections. Note that I inserted "Summarize custom field" at the end of the sample set.  
  • edited October 2
    Im not sure how to delete unwanted tables with a single standard entry but it wont affect number of sign offs since its displayed twice but only signed once. You could try changing the filter conditions instead of between R01 and R02 try separate lines. So 2 conditions. First line: Label = R01 second line:Label = R02. That way both labels must be present for table to generate. Similar with labels R02 and R03 etc. I havent tested this though. You may need to also try Label =R01 ...or Label =R02 you are allowed up to 3 "or" conditions on the same line. This "or" setup to specify the 2 labels must be present, alternatively adding separate lines as above. One of these layouts may suit your needs.

    For your other calculation, the Amount field in Empower calculates by dividing sample area by average bracketing standard area and multiplying this value by whatever is in the Value tab of component editor then by the Purity tab then multiplying this value by Dilution and dividing by Sampleweight in the sample set. If you have no values populated for these fields put 100 in the Value or Dilution to get your result. But its unlikely you dont already have relevant values here to account for dilutions, concentrations etc so in that case some CFs would be required.
  • As for the table issue, I tried "separate lines" and "or" setup; however, none of option worked for me. When I used "separate lines" for each label and select "equal" setup ("Equal" and "=R01" for first line; "Equal" and "=R2" for second line), I did not see any result table in the report. When I use "or" setup ("Equal", "=R01" "or" "=R02"), it was the same issue I had with "between" setup (unwanted table with a single standard entry). 

    As for the relative area calculation, your advice was very helpful. In the component editor in the sample set, I added value of standard as "1". Then, I created a CF "Amount/Dilution*100" to calculate the % relative area because some samples require dilution.  

    Thank you so much for your help! 
  • Im glad it helped. As for the table issue, your only option that i can see it to leave the report as i originally advised, with the between R01 and R02 etc conditions etc and delete the tables you dont need in advance depending on how many bracketing standards you need. A bit protracted but better than blank tables.
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