iSTAT trop compared to Trop I HS

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Our lab recently switched to the HS trop method. Being in POC, I'm sadly finding out my iSTAT trop doesn't correlate well with this-different units, different reference intervals, sensitivity is different, used differently...That being said, am I correct in thinking since the iSTAT trop is a non-waived test, it still needs a biannual correlation? How is this being done? Currently the positive threshold we have is >0.03, which I found out from Abbott is pretty low. They suggest >0.08 which is what most are using (?) If the positive threshold was changed would that make a difference? 
Feels like I'm trying very hard to compare apples to oranges.
Any info would be appreciated! Thanks so much.

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Can you do a unit conversion and see if that makes it better? 

I did that. The lab has the normal range of HS as less than 60 ng/L. The conversion of ISTAT trop 0.03ng/mL would still be 30 ng/mL. Does anyone have a iSTAT positive cutoff as >0.06 ng/mL?
That aside, I question if a comparison needs to be done due to what CAP says and since it's a non waived test, I'm fairly sure it needs a 6 month comparison.

Could you do it as more of a truth table type thing?  For example, take the results for each method and see if they compare within low, normal or high?  (If it's in the same range for both, for example, in the low range, it would show agreement.)  I'm not sure if this would work but thought I would throw it out there to see if it was an option.  I have an example if you would like me to send it to you - just let me know.

You will need to do a concordance. More in line with positive/negative comparisons. I can send an example if you like

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Melisa Wagoner
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