From Siddhartha Sharma: Can you please throw some light on the concept of AMR and CRR for coagulation testing instruments? Thanks.
I went to Dr. Larry Brace, Edward Hospital in Naperville, IL for this question. He responds that a current CAP requirement is for each assay to have an established analytic measurable range (AMR) and a clinical reportable range (CRR). That is, the AMR is how high your assay can measure and still be reportable (linear) before making a dilution. The CRR is how high you want to report. The CRR can be the same as the AMR, or you can dilute; CRR defines this. In some assays, you can dilute infinitely until you get something that falls into the AMR before accounting for dilution. In other assays, matrix changes define how far you can dilute. If you can only dilute 2x before you run into matrix effects, the the CRR is 2 times the AMR. I hope this is helpful.
Thank you, Larry, this explains it for me. Of course, the AMR and CRR would need to be defined for each assay and instrument. Geo.