(288 days)
The George King Coumadin® Plasma is an assayed control plasma derived from a single donor on Coumadin® therapy and is intended for in vitro diagnostic use in monitoring the accuracy of the coagulation analyzer and thromboplastin using the clottable prothrombin time/INR on an optical instrument with appropriate commercial reagents. George King Coumadin® Plasma may be used when evaluating a new lot of thromboplastin reagent or new coagulation analyzer.
Each lot of George King Coumadin® Plasma is from a single human donor stabilized on at least 6-weeks of Coumadin® therapy. The donor plasma is obtained via plasmapheresis using 4.0% sodium citrate and frozen immediately at -70°C.
The INR of the donor plasma is determined using the ACL Top 500 using RecombiPlastin 2G and each plasma is then categorized into one of the three INR levels of control material based on the testing results obtained using the following INR calculation: INR = (Patient PT / Mean of normal range) ISI.
Level 1 - INR Control: 1.5-2.8
Level 2 - INR Control: 2.9-4.0
Level 3 - INR Control: >4.0
The George King Coumadin® Plasma is an assayed control plasma for in vitro diagnostic use in monitoring the accuracy of coagulation analyzers and thromboplastin using the clottable prothrombin time/INR.
Here's an analysis of the acceptance criteria and the study that proves the device meets them:
1. Table of Acceptance Criteria and Reported Device Performance
| Performance Characteristic | Acceptance Criteria | Reported Device Performance |
|---|---|---|
| Precision (INR) | Total CV 4.1: Total CVs 1.54%-1.66% (met) | |
| Precision (Protime) | Total CV 4.1: Total CVs 1.58%-1.69% (met) | |
| Reproducibility (INR) | Total CV 4.0: Reproducibility CVs 2.68%-4.26% (met) | |
| Reproducibility (Protime) | Total CV 4.0: Reproducibility CVs 2.73%-4.30% (met) | |
| Open Vial Stability | Pre-determined acceptance criteria (not specified numerically) | Stable for 6 hours at 19-22°C (met) |
| Shelf-Life Stability | Real-time testing on-going to update shelf-life | Current claim of 6 months at -70°C |
2. Sample Size Used for the Test Set and Data Provenance
- Precision Study: For each of the three INR ranges, three different lots of GK Coumadin® Plasma were tested. For each lot, 80 replicates (n=80) were analyzed (20 days with 2 runs per day and 2 replicates per run). The study was conducted in-house. Data provenance is therefore in-house, prospective testing.
- Reproducibility Study: For each of the three INR ranges, three different lots were tested. For each lot, samples were assayed for 5 days, one run per day, for a total of N=75 samples. This study was performed across three different clinical laboratories, implying prospective, external data, presumably from the US.
- Stability Studies: Three lots of GK Coumadin® Plasma were used for both open vial and shelf-life stability studies. Data provenance is in-house, prospective testing.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
This information is not provided in the document. The studies conducted are analytical performance studies (precision, reproducibility, stability) for a control plasma, not diagnostic accuracy studies that rely on expert ground truth. The "ground truth" here is the measured INR or Prothrombin Time value.
4. Adjudication Method for the Test Set
This information is not applicable as the studies are analytical performance studies of a control material and do not involve human diagnostic interpretation or adjudication of results.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done
No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not done. This type of study is typically performed for diagnostic devices where human readers interpret medical images or data. The George King Coumadin® Plasma is a control material for laboratory instruments.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done
Yes, the studies presented (precision, reproducibility, stability) evaluate the performance of the device (George King Coumadin® Plasma) in a standalone manner, as measured by laboratory instruments (ACL TOP series) using specified reagents (RecombiPlastin 2G). There is no "human-in-the-loop" component being evaluated for the performance of the device itself; rather, it is a control used to monitor the accuracy of an instrument.
7. The Type of Ground Truth Used (expert consensus, pathology, outcomes data, etc.)
The ground truth for the performance studies is the measured INR and Prothrombin Time values obtained from the specified laboratory instruments and reagents. For the initial categorization of donor plasma into INR levels, the INR was determined using the ACL Top 500 and RecombiPlastin 2G.
8. The Sample Size for the Training Set
There is no explicit mention of a separate "training set" in the provided document. The development of a control plasma does not typically involve a machine learning algorithm that is trained on a dataset. The document describes the manufacturing and analytical validation of a control material.
9. How the Ground Truth for the Training Set Was Established
As there is no explicit training set mentioned for an algorithm, the concept of "ground truth for the training set" is not applicable in the context of this device. The INR of the donor plasma is determined by standard laboratory methods using a calibrated instrument for categorization into control levels.
§ 864.5425 Multipurpose system for in vitro coagulation studies.
(a)
Identification. A multipurpose system for in vitro coagulation studies is a device consisting of one automated or semiautomated instrument and its associated reagents and controls. The system is used to perform a series of coagulation studies and coagulation factor assays.(b)
Classification. Class II (special controls). A control intended for use with a multipurpose system for in vitro coagulation studies is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 864.9.