I routinely monitor Pat Letendre’s bulletin board service, Medlab-L, and lately there has been a thread discussing whether to report the INR alone or with the prothrombin time. Here is a comment from Dave McGlasson that I found to be helpful.
Many have questions about reporting out either the PT with the INR or just the INR. At one institution I am involved with they report out only the INR result. The reason for this is when they went to a more sensitive thromboplastin the results were a little longer than the physicians were used to getting. Consequently the surgeons ordered a lot of FFP pre-op. So we started only reporting the INR values and the requests for FFP dropped off about 90%. Frankly I wish we could report out both because there are many conditions that the INR is not suitable for use. However, we do make available a conversion table for the PT to INR value.