Trm.31450

[ABQ bloodbanker]

You are correct: it does not correlate gel to liss to peg to enzymes to Prewarmed or using adsorbed plasma. The answers would vary too much, depending on what antibody you were testing.

Denise

I interpret this checklist only applies to the following tests: Blood group and Rh typing, antibody screen, DAT , phenotyping test between different methodologies and it does not apply to the different tests used for antibody investigation because different situations will dedicate which method to be used. Please comment.

[Deny Morlino]

I would like to ask about the instrument part of “If the laboratory uses more than one instrument/method to test for a given analyte, are the instruments/methods checked against each other at least twice a year for correlation of results?â€

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We validate and check the instruments in the Blood Bank and all is well.

However, when the down-time of a machine is long we have had to use the one at the Serology Section. Now, they do their own validations and cross checks and we are all as one Lab Accredited. Yet, one inspector told me that I should not use any instrument that my section, the Blood Bank, has not validated and cross checked. Is that so?

Thank you

Liz

Any analyzer used as a "backup" should be validated with the primary has always been our approach. When we upgraded the blood gas analyzer and hemoglobin results became available we validated the results with both the primary and backup hematology analyzer. This was as much a just in case manuver in case someone on 2nd or 3rd shift decided to give the hgb from the blood gas analyzer out (you just know it will happen at some point). It sounds like you have a need to validate performance with the analyzer in blood bank with the one in the Serology Section. Just my take on it.

[Liz]

Thank you Deny, it makes sense.

Liz

[MAGNUM]

We just had our CAP survey, and this Question was the only deficiency that was found in my department. I had actually answered this as because we test our QC in both tubes and gel each day, I was under the assumption that this would be sufficient, but we all know what assuming does. The answer that I received from my surveyor was that because QC materials are manufactured these cannot be used for the validation/correlation studies. What was suggested by my surveyor and also another aquaintence who is a AABB surveyor is to test a couple of samples every 2 to 3 weeks or so so that there is continuous testing occuring which in their oppinion looks better to the surveyor than only performing this twice a year.

[DPruden]

We managed not to get cited on this in June. So, what are people doing when the methods don't correlate and we all know they won't in some instances?

[Eagle Eye]

as long as you are able to compare both methods and have explanation if they do not corelate, have MD signe off on it...you are OK.

eg. You have a specimen with three antibody id'd by gel and when you test same sample by tube and id two out of three and able to prove that tube is less sensitive and did not pick up third antibody...you will be OK. CAP says whatever you do have a summary and your medical director must sign off on it and you will be in compliance.

[MeganPLT]

We correlate all of our tests that are performed using different methodology. Blood types, we get one of every ABORH (8 total) and run in tubes and gel, for example. We also correlate the same methodology (Antibody screens, for instance) that we run manually and on the ProVue. And then, we have 3 ProVues, so we correlate all 3 ProVues.

I have attached my parity procedure with a nice form I document all results from all locations/instruments. We do this every 6 months.

Denise

Thank you so much for sharing your procedure and form, it is very nicely done!

I am curious to know if you have been CAP inspected yet, and if your correlation studies were acceptable?

[Stoogiesfreak]

Hi Malcolm,

We do our correlations between the Tango and tube method every 6 months. We also use "inhouse" QC for the Tango and that is another weekly correlation as we type samples used for QC on the Tango and with the tube method.

Another question:

We do the automated CAP survey JAT on the Tango. Can we use the JAT survey as an adequate method for proficieny testing with the tube method? I don't really want to purchase two seperate surveys, but if I need to I will. Also, what about antigen typing as it is not offered on the Tango JAT survey.

Thanks - as always I look forward to your expertise!

Regards,

John

[tbostock]

We compare all methods that we use here (Tango, gel, and manual) for every test that we perform. We do this every 6 months. And then when they don't correlate (which they sometimes don't) we write an explanation that solid phase and gel are more sensitive to certain tests compared to the tube method. A little annoying doing a correlation that won't correlate, but that's what the regulatory agencies want you to do.