(60 days)
The microINR System measures prothrombin time (PT) expressed in International Normalized Ratio (INR), for monitoring oral anticoagulant therapy with warfarin.
The microINR System consists of a meter and chips (test strips) and uses fresh capillary whole blood from a fingerstick. The microINR System is intended for patient self-testing use as well as for healthcare professionals at Point of Care settings.
The microINR System is intended for use in patients 18 years old or older. Patients must be stable on warfarin medication for at least 6 weeks before starting to use the microINR System.
For self-testing use: The system is intended for properly trained users under specific prescription of a physician.
Caution: The microINR System is not intended for use in patients who are transitioning from heparin treatment to warfarin therapy. The microINR System is not intended to be used for screening purposes.
The microINR System is comprised of a portable measuring device (microINR, microINR Link and microINR Expert meter) and test strips (microINR Chips) in which the capillary blood sample flows through capillary action.
The microINR Chip contains a reagent in dried form which consists of thromboplastin, and contains two symmetrical regions, the measuring channel and a control channel. The microINR meters measure International Normalized Ratio (INR) based on a Prothrombin Time (PT) assay carried out in the microINR Chip based on microfluidic technology with machine vision detection.
The microINR System has a multi-level On-board Quality Control. Multiple key functions and elements of the system are checked and if deviations are detected, error messages are displayed and test results are not reported.
The microINR System measures prothrombin time (PT) expressed in International Normalized Ratio (INR) for monitoring oral anticoagulant therapy with warfarin.
Here's an analysis of the acceptance criteria and the study that proves the device meets them, based on the provided FDA 510(k) clearance letter:
1. Table of Acceptance Criteria and Reported Device Performance
The document does not explicitly state pre-defined "acceptance criteria" in terms of specific thresholds for slope, intercept, Pearson correlation, SD, or CV%. Instead, it presents the performance characteristics demonstrated by the studies. The comparison to predicate devices, and the conclusion of substantial equivalence, imply that these reported performance values were considered acceptable.
| Metric | Acceptance Criteria (Implied) | Reported Device Performance |
|---|---|---|
| Accuracy (microINR System vs. Lab Reference) | Strong correlation (r ≈ 1), small bias (slope ≈ 1, intercept ≈ 0) | N: 1016, Slope: 1.00, Intercept: 0.08, Pearson (r): 0.97 |
| Accuracy (Self-testing patients vs. Lab Reference) | Strong correlation (r ≈ 1), small bias (slope ≈ 1, intercept ≈ 0) | N: 248, Slope: 0.95, Intercept: 0.13, Pearson (r): 0.97 |
| Accuracy (Self-testing patients vs. HCPs using microINR System) | Strong correlation (r ≈ 1), small bias (slope ≈ 1, intercept ≈ 0) | N: 461, Slope: 0.99, Intercept: 0.02, Pearson (r): 0.98 |
| **Precision (INR |
§ 864.7750 Prothrombin time test.
(a)
Identification. A prothrombin time test is a device used as a general screening procedure for the detection of possible clotting factor deficiencies in the extrinsic coagulation pathway, which involves the reaction between coagulation factors III and VII, and to monitor patients receiving coumarin therapy (the administration of one of the coumarin anticoagulants in the treatment of venous thrombosis or pulmonary embolism).(b)
Classification. Class II (performance standards).