Is there a widely used (most current) calculation that is successful at interpreting inhibitor vs factor deficiency. Wanted to see what you would use to determine mixing study results, both prothrombin time (PT) and partial thromboplastin time (PTT), when comparing results to patient normal PT and PTT reference ranges. If not can you provide literature resource that offers options.
Hello, and thank you for your question. We’ve had several discussions about mixing studies, mostly related to the PTT, that can provide you with the answer, let me link you to one of our more recent posts, “Mixing Studies: 4:1?” This message in turn links you to a recent Quick Question asking about a standard correction limit.
I advocate for the Rosner Index as being the most consistent and scientifically defensible approach. Though you’ll typically see the Rosner Index applied to the PTT, it can also be used for PT mixing studies. I hope this helps!