CoaguChek and Coag-Sense PT2 Meter Point of Care INR Device Validation

Area of Science:

• Clinical Chemistry
• Medical Devices
• Pharmacology

Background:

• Warfarin therapy requires regular monitoring of the international normalized ratio (INR) to ensure efficacy and safety.
• Accurate INR measurements are crucial for preventing thromboembolic events and bleeding complications.
• Standardizing point-of-care (POC) INR testing can improve data integrity and facilitate electronic result transmission.

Purpose of the Study:

• To evaluate the performance of two commercially available POC INR devices against a plasma INR reference method.
• To assess the concordance, bias, and dosing decision accuracy of POC INR devices for warfarin monitoring.
• To determine the suitability of POC devices for electronic result transmission and standardized INR measurements.

Main Methods:

• A multicenter study compared the Coag-Sense PT2 Meter and CoaguChek XS Pro/Plus devices against an internal plasma INR reference method.
• Two hundred ninety-nine warfarin-treated patients were enrolled across three Mayo Clinic sites.
• Bias, linear regression analysis, and dosing decision accuracy were assessed for each POC device.

Main Results:

• The CoaguChek devices showed higher concordance with plasma INR, with 95.3% of values within 0.4 INR units (R²=0.93).
• The Coag-Sense device had lower concordance, with 60.2% of values within 0.4 INR units (R²=0.83).
• Appropriate dosing recommendations based on plasma INR were achieved for 97.7% of CoaguChek results versus 81.6% for Coag-Sense.

Conclusions:

• The CoaguChek devices demonstrated less systematic bias and greater concordance with plasma INR compared to the Coag-Sense device.
• POC INR devices, particularly CoaguChek, offer a reliable alternative for warfarin monitoring, enabling accurate dosing decisions.
• These findings support the use of CoaguChek devices for standardized INR measurements and electronic result transmission in clinical practice.