PT/INR correlation using Werfen Signature Elite and Stage

You can collect 2 samples (the one that is acceptable for each instrument you are correlating). Regardless of the instrument the PT/INR should be within reasonable range. You have to established the acceptability criteria because you are not comparing apple to apple, therefore the numbers should not be identical but if your criteria is enough it should pass. Read the package insert of the product you are using, usually at the back it will tell you what they compare it to with when they validated the product and it should say the precession and accuracy of the product you are using. Use that to guide you.

Use Proficiency testing results from CAP or API as you have multiple instrument listing and they provide the acceptable limit. You can use the limit as your acceptability criteria if your medical director agree to it.

Sincerely,
Alma
“Far and away the best prize that life offers is the CHANCE to work hard at work worth doing” – Theodore Roosevelt

Alma Calzado-Knudson, MBA, CLS, MT (ASCPi & AMT)
Manager, Lab Quality and Point of Care Testing
Student Education Coordinator
[cid:image001.png@01DB9831.AF473320]
[cid:image002.png@01DB9831.AF473320]1531 Esplanade Chico CA 95926
•530-332-7360 (Main Lab) l 530-332-7362 (Direct) l 254-722-5388 (Mobile) / [cid:image003.png@01DB9831.AF473320] 530-893-6809
• alma.calzadoknudson@enloe.org
“Together you and I will Each Accomplish More as we WORK towards achieving a common goal – Patient Safety and Satisfaction”