(108 days)
The STA® -Liatest® vWF test kit is intended for use with the STA® analyzer to perform quantitative assays of von Willebrand Factor (vWF) antigen in citrated plasma by the immuno-turbidimetric method based on the measurement of fight absorbance produced by a suspension of microlatex particles coated with specific anti-vWF antibodies.
Each STA®-Liatest vWF test kit provides: 4 x 5-ml vials of ready-for-use glycine buffer; 4 x 2-ml vials of a suspension of microlatex particles coated with rabbit antihuman vWF antibodies; 4 x 4-ml vials of diluent solution containing glycine for dilution of the latex reagent before use.
Reagents in intact vials remain stable for 18 months after the date of manufacture, when stored at 2°-8°C. After opening of the vials or after dilution, kit reagents are stable for 15 days on board the STA® analyzer.
I am sorry, but the provided text from K96X625 does not contain the detailed information necessary to answer your request. The document is a 510(k) premarket notification for a medical device from 1990, and it focuses on demonstrating substantial equivalence to an existing device rather than providing a detailed study design with acceptance criteria, sample sizes, expert qualifications, or ground truth establishment as would be present in a more modern clinical study report.
Specifically, the text is a Safety and Effectiveness Summary and only states:
- Intended Use: Quantitative assays of von Willebrand Factor (vWF) antigen in citrated plasma by an immuno-turbidimetric method using the STA® analyzer.
- Components: Description of the kit contents (buffer, microlatex particles with antibodies, diluent).
- Stability: Shelf life of unopened and opened/diluted reagents.
- Substantial Equivalence Claim: "The proposed STA®-Liatest® vWF test kit has demonstrated substantial equivalence to the commercially available ASSERA®-PLATE vWF kit (Diagnostica Stago, France; K861417) which is an electro-immunodiffusion procedure for the quantitative determination of vWF antigen levels in citrated plasma."
The document does not provide information on any of the following, which are crucial for your request:
- Acceptance criteria and reported device performance: While it claims substantial equivalence, it doesn't list specific performance metrics (e.g., sensitivity, specificity, accuracy, precision, correlation coefficients) or the thresholds for those metrics that were considered "acceptable."
- Sample size, data provenance: No details on the number of samples, where they came from, or if they were retrospective/prospective.
- Number/qualifications of experts, adjudication method: This would not typically be relevant for a lab-based immunoassay unless there was a subjective interpretation component, which isn't indicated. However, there's no mention of any expert involvement for establishing ground truth.
- MRMC comparative effectiveness study: This is not applicable to an in vitro diagnostic (IVD) device like a vWF test kit. MRMC studies are typically for image-based diagnostic aids or AI algorithms that assist human interpretation.
- Standalone performance: While the device has standalone performance (it generates a quantitative vWF value), the document doesn't provide specific performance metrics in isolation from the comparison to the predicate.
- Type of ground truth: Not explicitly stated, but for a quantitative assay, the "ground truth" would generally be established by a reference method or highly characterized samples, which is not detailed here.
- Training set sample size and ground truth establishment (for AI): This is not an AI device, so these concepts are irrelevant to the provided text.
To answer your questions as specified, you would need a detailed study report or clinical trial results for a more modern device, especially one involving AI or subjective interpretation. This document is too high-level and focused on regulatory equivalence for an IVD from 1990.
§ 864.7290 Factor deficiency test.
(a)
Identification. A factor deficiency test is a device used to diagnose specific coagulation defects, to monitor certain types of therapy, to detect coagulation inhibitors, and to detect a carrier state (a person carrying both a recessive gene for a coagulation factor deficiency such as hemophilia and the corresponding normal gene).(b)
Classification. Class II (performance standards).