INR
Your prothrombin time expressed on a standard scale.
Calculated from the PT result so that clinics can compare across labs.
This one isn’t a test
INR = (Patient Prothrombin Time ÷ Control PT) raised to the ISI
No extra sample was taken for this and no extra assay was run. It is arithmetic on numbers already on your report — but it still adds a line to the advertised test count.
Computed from Prothrombin Time.
That does not make the number useless — eGFR is calculated and doctors act on it every day. It means it should not be counted as a separate test when you are comparing what a package costs.
How we rate it — Useful
Worth doing for a specific reason — a risk factor, a symptom, an age group.
This rating and the description above were written against published screening guidelines by someone who is not a clinician, and are awaiting review by one. We would rather say that than imply an authority we do not have.
Check-ups that include it
None of the health check-up packages we track include this test.
Also sold as
Every one of these names refers to this same test. Resolving them to one canonical entry is what makes an honest comparison possible.
inr · international normalized ratio · prothrombin ratio
Information here is for comparing packages, not for diagnosing yourself. Talk to a doctor about which tests you actually need.