Total hemoglobin Comparison: Struggling to meet 4% cut off between Avoximeter and Hematology analyzer

We don't report the THB from the AVOX. 

Hello Riya, we compare ours to the ABL 90 in respiratory therapy. That way same specimen type is ran.

That's one of the reasons we also do not report tHb from the AVOX. For some reason we were still reporting it on our proficiency testing and we failed all 5 samples in the first survey of 2025 w/ the new acceptability. I've now ceased reporting that. 

We run comparisons with the Avox 1000e with our Siemens Rapid Point.

Correct me if I am wrong please - the acceptability criteria is for proficiency testing from what I understand.  Your medical director can determine what your acceptability criteria is.  It doesn't have to match that proficiency testing value, but many of us do use that.  Our medical director decided to keep the 4% for only when comparing between the same make & model instruments, but if comparing across different methods or analyzer platforms, we are going to keep our 7% criteria.

We do not report the thb, however, we do run comparisons with the GEM 5000 in Respiratory just to ensure we are within allowable error because the thb is used to calculate the %O2Hgb

@ Miranda Cotter - We use a similar approach as you described.  Based on retrospective comparisons I did not think the inter-method comparisons would meet the new +/-4% acceptability criteria per CMS, so we are continuing the +/-7% acceptability criteria for comparisons between different methods or analyzer platforms.  Meeting +/-4% acceptability criteria for tHb comparisons using the same methodology may still be a challenge.

You're correct! The acceptability criteria for proficiency testing are often set by external organizations like CAP (College of American Pathologists), but your medical director can indeed determine the criteria that best suit your specific needs and circumstances.

Many labs adopt the proficiency testing criteria for consistency but adjust them internally based on practical considerations. For instance, using 4% for comparisons within the same make and model, and 7% for different methods or platforms, as your medical director decided, is a common practice.

This flexibility allows labs to tailor their quality control processes to better fit their operational realities while still maintaining high standards of accuracy and reliability.

Question for those that use the AVOX 1000E and don't report the THb/removed it from their CAP activity menu. Have you found a way to suppress the result from being displayed on the instrument? If it can't be suppressed from the view, is there any concern of a questionable/critical value being displayed, the care team acting on it and using that result to guide treatment of the patient?

Agree with previously said - you don't need to adopt the 4%, it is up to your MD to decide what criteria to use.  We use 15%, as our comparisons for Avox are often against other different methodology like the lab Hematology machines.  4% is too tight when you are using different platforms.  

Thank you so much everyone - your responses have been incredibly helpful. I truly appreciate it.