I received this question from Emily Oakley at Windy Hill. Emily also posted this question to Pat LeTendre’s Medlab List last week: “How high should INRs be reported?” Emily, fortunately, this was the subject of a Quick Question in August of 2008. Please select the link for a summary of our findings at that time. I’d also like to point you to Olson JD, Brandt JT, Chandler WL, et al. Laboratory reporting of the international normalized ratio: progress and problems. Arch Pathol Lab Med 2007;131: 1641-7. The article sets the maximum reportable INR at 9.0 Thank you for your valuable question. Geo.