(28 days)
The MYO TestPak used on the Stratus® CS STAT Fluorometric Analyzer is an in vitro diagnostic product for the measurement of myoglobin in heparinized plasma. Measurements of myoglobin are used as aids in the rapid diagnosis of renal and heart disease, e.g. acute myocardial infarction.
The MYO TestPak consists of a plastic cartridge with five wells and a small square of glass fiber paper embedded in it. The method utilizes a two-site sandwich assay based upon solid phase Radial Partition Immunoassay (RPIA) technology. In this procedure, dendrimer linked monoclonal antibody is added to the center portion of a square piece of glass fiber paper in the MYQ TestPak. Sample is then added onto the paper where it reacts with the immobilized anti-myoglobin antibody. After a short incubation, a conjugate consisting of enzyme-labeled antibody directed against a distinct antigenic site on the myoglobin molecule is pipetted onto the reaction zone of the paper. During this second incubation period, enzymelabeled antibody reacts with the bound myoglobin, forming an antibody-antigen-labeled antibody sandwich. The unbound labeled antibody is later eluted from the field of view of the Stratus® CS analyzer by applying a substrate wash solution to the center of the reaction zone of the TestPak. By including substrate for the enzyme within the wash solution, initiation of enzyme activity occurs simultaneously with the wash. The enzymatic rate of the bound fraction increases directly with the concentration of myoglobin in the sample. The reaction rate is measured by an optical system that monitors the reaction rate via front surface fluorescence. All data analysis functions are performed by the microprocessor within the analyzer.
The provided text focuses on the premarket notification (510(k)) for a medical device called the "Stratus® CS Myoglobin (MYO) TestPak." The key purpose of this submission is to demonstrate substantial equivalence to a previously cleared device, specifically concerning a change in the recommended frequency of quality control (QC) testing from daily to weekly.
Here's an analysis based on your requested information, highlighting what is available and what is not in the provided text:
1. A table of acceptance criteria and the reported device performance
The document does not explicitly state "acceptance criteria" in a quantitative sense for overall device performance. Instead, the core "acceptance criteria" for this specific submission is that the change in QC frequency does not adversely affect the performance of the device, and that the device remains substantially equivalent to its predicate.
The reported device performance, in the context of this submission, is qualitative: "The QC data collected supports the recommended change in QC frequency and indicates the change will not adversely affect performance of the device." No specific numerical performance metrics (e.g., sensitivity, specificity, accuracy, precision) from a new study are provided, as the submission relies on the established performance of the predicate device and the new QC data's non-inferiority.
| Acceptance Criteria (Implicit for the QC frequency change) | Reported Device Performance (Regarding QC frequency change) |
|---|---|
| The change in recommended QC frequency (from daily to weekly) does not adversely affect the performance of the device. | "The QC data collected supports the recommended change in QC frequency and indicates the change will not adversely affect performance of the device." |
| The device remains substantially equivalent to the predicate device despite the change in QC frequency. | Conclusion states, "Both assays are in vitro immunoassays with intended uses for the measurement of Myoglobin in heparinized plasma. The modified device differs from the device cleared under K981102 only in the recommended QC frequency in product labeling." and "Comments on Substantial Equivalence: ... The QC data collected supports the recommended change in QC frequency and indicates the change will not adversely affect performance of the device." |
2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
The document does not specify the sample size used for the QC data that supported the change in frequency, nor does it detail the provenance of this data (e.g., country of origin, retrospective or prospective). It simply refers to "The QC data collected."
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)
Not applicable. This device is an in vitro diagnostic (IVD) for measuring myoglobin, which is a quantitative biochemical measurement. The "ground truth" for the performance of such a device is typically established through reference methods, certified calibrators, and statistical analysis of assay performance (e.g., precision, linearity, accuracy against known standards), rather than expert consensus on images or clinical cases.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
Not applicable. As described in point 3, this is an IVD for quantitative measurement. Adjudication methods like 2+1 or 3+1 are typical for subjective interpretations (e.g., image reading) where multiple experts resolve disagreements.
5. If a multi reader multi case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance
Not applicable. This is not an AI-assisted device, nor is it a device that involves human readers interpreting results in a way that an MRMC study would be relevant. It's an automated IVD system providing a quantitative biochemical result.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
This is an automated in vitro diagnostic device, so its primary operation is "standalone" in terms of performing the assay and generating a quantitative result. The submission is not about an algorithm, but rather a chemical assay system. No specific study details of a standalone performance evaluation (beyond the predicate device's established performance) are provided, as the submission focuses on the implications of changing QC frequency.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
For an in vitro diagnostic device measuring a biomarker (myoglobin), the "ground truth" for its analytical performance is typically established by:
- Reference methods: Comparing results to a gold standard analytical method.
- Certified reference materials/calibrators: Samples with precisely known concentrations of myoglobin.
- Split sample comparisons: Testing samples against a legally marketed, validated device.
The document does not detail specific "ground truth" types used for the original validation of the predicate device, nor for the QC data supporting the frequency change, but these would be the standard approaches for such a device.
8. The sample size for the training set
Not applicable. This device does not involve machine learning or AI models that require a "training set." It is a chemical assay system.
9. How the ground truth for the training set was established
Not applicable, as there is no training set for this type of device.
§ 866.5680 Myoglobin immunological test system.
(a)
Identification. A myoglobin immunological test system is a device that consists of the reagents used to measure by immunochemical techniques the myoglobin (an oxygen storage protein found in muscle) in serum and other body fluids. Measurement of myoglobin aids in the rapid diagnosis of heart or renal disease.(b)
Classification. Class II (performance standards).