(104 days)
The microINR System measures prothrombin time (PT) expressed in International Normalized Ratio (INR), for monitoring oral anticoagulant therapy with warfarin.
The microlNR System consists of a meter and chips (test strips) and uses fresh capillary whole blood from a fingerstick. The microlNR System is intended for patient self-testing use as well as for healthcare professionals at Point of Care settings.
The microlNR 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 in patients who are transitioning from heparin treatment to VKA therapy. The microINR System is not intended to be used for screening purposes.
The modified device microINR System containing the microINR Expert Meter is derived from the existing devices microINR Meter and microINR Link Meter. The change is for the incorporation of additional connectivity functions (Wi-Fi and Ethernet connectivity on top of the Bluetooth connectivity of the microINR Link), a touchscreen, a barcode scanner as well as other configurable settings and optional functions (such as the option of including operator and patient identification). All the actions related to the extra functionalities and configurable settings are set before or after performing the analytical test. The fundamental scientific technology of the modified device and its performance has not changed. No performance changes to the microINR System have been implemented since its initial clearance on K180780 and its home use clearance in K201185.
The provided text is a 510(k) summary for the microINR System, specifically addressing changes made to the device (the incorporation of the microINR Expert Meter). The key takeaway from the document is that the fundamental scientific technology and performance of the device have NOT changed. The modifications primarily involve connectivity, user interface, and optional features.
Therefore, the document does not present new performance data based on a new study for the microINR System's core functionality (measuring PT/INR). Instead, it relies on the performance previously cleared under K180780, K201185, and K231711. The testing described in section 7 ("Testing on the modified device was conducted as follows: Software verification and validation; testing for Radiofrequency, Electromagnetic Compatibility and Electrical Safety: Cybersecurity analysis and testing; and Usability testing.") relates to the new functionalities added to the expert meter, not the core PT/INR measurement.
Given this, I cannot extract numerical "acceptance criteria" and "reported device performance" directly from this document for the PT/INR measurement. The document states:
- "No performance changes to the microINR System have been implemented since its initial clearance on K180780 and its home use clearance in K201185."
- "The fundamental scientific technology of the modified device and its performance has not changed."
- "The performance characteristics of the microINR System remain the same."
Therefore, for the purpose of answering your request based solely on the provided text, the answer will reflect that the core performance information is not detailed here, as the submission focuses on documenting that the new components do not negatively impact the already cleared performance.
Here's the information based on the provided text, with explicit notes where information is not available or where the focus is on the new functionalities rather than the core PT/INR measurement:
Acceptance Criteria and Device Performance for microINR System (Focus on New Expert Meter Functionalities)
The provided 510(k) summary for the microINR System (K243543) primarily addresses changes related to the incorporation of the "microINR Expert Meter," which introduces additional connectivity, a touchscreen, barcode scanner, and other configurable settings. The document explicitly states that the fundamental scientific technology and the performance of the device related to its intended use (measuring Prothrombin Time/INR) have not changed from previous clearances (K180780, K201185, K231711).
Therefore, the "study" described in the document primarily focuses on verifying and validating these new functionalities to ensure they do not introduce new questions of safety or effectiveness, rather than re-evaluating the core PT/INR measurement accuracy.
1. Table of Acceptance Criteria and Reported Device Performance
As the core performance of the PT/INR measurement is stated to be unchanged and reliant on previous clearances, a specific table of numerical acceptance criteria and reported new performance for PT/INR is not present in this document. The testing detailed pertains to the new functionalities of the Expert Meter. The acceptance criteria for these new functionalities are broadly stated as:
| Acceptance Criterion Type (for new functionalities) | Reported Device Performance (for new functionalities) |
|---|---|
| Software verification and validation | All testing results met the pre-determined acceptance criteria. Performed as intended. |
| Radiofrequency, Electromagnetic Compatibility, Electrical Safety | All testing results met the pre-determined acceptance criteria. Performed as intended. |
| Cybersecurity analysis and testing | All testing results met the pre-determined acceptance criteria. Performed as intended. |
| Usability testing | All testing results met the pre-determined acceptance criteria. Performed as intended. |
| Risk analysis of implemented changes | No significant detectable risks compared to predicate device; all residual risks deemed acceptable. |
2. Sample Sizes Used for the Test Set and Data Provenance
The document does not specify quantified sample sizes for the testing of the new functionalities. It generally refers to "Software verification and validation; testing for Radiofrequency, Electromagnetic Compatibility and Electrical Safety: Cybersecurity analysis and testing; and Usability testing."
Data provenance (e.g., country of origin, retrospective/prospective) for these specific verification and validation activities is not detailed.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Their Qualifications
Given that the document focuses on technical verification (software, electrical, cybersecurity) and usability of new features (connectivity, touchscreen, barcode scanner), and not the diagnostic accuracy of PT/INR measurement, the concept of "experts establishing ground truth" in the clinical sense (e.g., radiologists for imaging) is not directly applicable here. The ground truth for these tests would be technical specifications and user expectations. The document does not specify the number or qualifications of personnel involved in these specific verification and validation activities.
4. Adjudication Method for the Test Set
Not applicable in the context of the described technical verification and validation of new functionalities. Adjudication methods like 2+1 or 3+1 are typical for clinical outcome or diagnostic accuracy studies involving human interpretation, which is not the focus of the testing described for this device's modifications.
5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study Was Done
No MRMC study was done or described in this document. This type of study is relevant for AI-assisted diagnostic tools where human reader performance is being evaluated, which is not the nature of the microINR System or the modifications herein.
6. If a Standalone (Algorithm Only Without Human-in-the-Loop Performance) Was Done
The microINR System is a point-of-care device that requires human interaction (fingerstick, applying blood, reading results). Therefore, a purely "standalone" (algorithm only) performance is not a direct concept for this type of device. The document states that the "fundamental scientific technology... has not changed," implying that the core measurement algorithm's performance remains as previously cleared. The current submission focuses on added functionalities (connectivity, display) to an already cleared system.
7. The Type of Ground Truth Used
For the new functionalities tested: The ground truth would be based on engineering specifications, software requirements, cybersecurity standards, and usability design principles. The document does not specify the exact methods or "ground truth" for each of these technical tests, only that they met pre-determined acceptance criteria.
For the core PT/INR measurement: This information would reside in the previous 510(k) submissions (K180780, K201185, K231711). Typically, ground truth for INR devices is established against a reference laboratory method (e.g., plasma-based PT/INR using a validated coagulometer).
8. The Sample Size for the Training Set
The document does not describe a "training set" in the context of machine learning model development. This device is an in-vitro diagnostic (IVD) device, not an AI/ML diagnostic tool that requires a training set for model development in the same way. The core measurement algorithm's development (if it had a "training" phase) would have occurred prior to the initial clearances.
9. How the Ground Truth for the Training Set Was Established
Not applicable as this is not an AI/ML device that uses a "training set" in the described context.
§ 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).