Method comparison

[Ehowell66]

Hi everyone,  

I am a new supervisor and I need a little help.   Our lab has two Echos, and we use gel and tubes also.    When doing comparison studies do I need to run my patients on both echos as well as the gel and tubes.  Also, we use the Echos, with tube and gel as back up for antibody identification.  Do we need to do comparison for antibody identification as well?   The previous supervisor had a procedure in place but what was being done was not satisfactory.  What is the rule for using CAP survey samples?.  ex  Echo to test antibody identification   The procedure we have in place states to run at least four patient samples,  how many do you run against all methods for the comparison studies?

Thanks in advance for all your help.   It can be a little overwhleming at times

[R1R2]

2 samples tested on both Provues, manual gel, peg, saline and prewarm.  No antibody identification.

AB+, neg screen

O-, pos screen

 

Don't forget your DATs if you use different methods

[David Saikin]

I use one CAP specimen/set of challenges.  Gel is my main method.  I check ABORh in tubes vs gel and I check PeG and LISS vs gel with the ab screen.  That is all I perform.

[tbostock]

You wouldn't need to do Ab ID if you are using the same methods as you do for your Ab screen. It's not reagent comparison, it's correlation of your methods.

Yes, you would have to do the correlation on both analyzers and in manual methods.

You should do correlations on all tests that you have that are performed by more than one method. See attached for our policy; I hope it helps you.

P.S. Don't feel bad about being overwhelmed; it's part of the job.

Correlation of Methods, 9-12.doc

Correlation of Methods Worksheet.xls

[goodchild]

Our policy is similarish to Terri's.

 

We do

ProVue vs Tube ABO/Rh.

ProVue vs manual gel vs tube AB Screen.

manual gel vs tube antibody ID.

manual gel vs tube DAT

Realistically we should include manual gel vs tube IAT crossmatch but I'm not too worried about it.

All patient samples. We choose a mix of positives/negatives based on the primary method of testing.

[carolyn swickard]

Just remember that you can not do comparison testing on CAP/API/etc proficiency materials until after the due date of the survey (or the date after which you can no longer change the answers).  Doing comparison testing before that will put you in violation of " treat the survey the same as the pt specimens", since you will be doing multiple testing on the specimen and might get a different answer.  Hopefully not as that would mean your methods were not correlating either!  Record the due date of the survey on your correlation form and then the date (a later one) that you do the correlation studies.  Some might recommended waiting until the survey answers come back, but the automated and manual BB surveys don't last as well as some of the other survey materials, so that might lead to some problems too. 

Good luck and welcome to the FUN!