(75 days)
The REAADS von Willebrand Factor Antigen (vWF:Ag) Test kit is an in vitro diagnostic assay for the quantitative determination of human plasma levels of vWF:Ag (as a percent assay to throncentration) by enzyme linked immunosorbent assay (ELISA). Plasma levels of vWF:Ag may be used as an aid in diagnosing von Willebrand disease.
The REAADS von Willebrand Factor Antigen Test Kit is a sandwich enzyme linked immunosorbent assay (ELISA). The capture antibody specific for human vWF is immobilized to 96-microwell polystyrene plates. Diluted patient plasma is incubated in the wells, allowing any available vWF:Ag to bind to the anti-human vWF antibody bound to the plastic. The plates are rinsed to remove any unbound plasma vWF:Ag molecules. Bound vWF:Ag is quantitated using an HRP conjugated anti-human vWF detection antibody. Any unbound conjugated anti-human vWF is washed away after an incubation period. A chromogenic substrate of tetramethylbenzidine (TMB) and hydrogen peroxide (H2O2) is added to develop a colored reaction. The intensity of the color is measured spectrophotometrically at 450nm in optical density (O.D.) units. vWF:Ag relative percent concentrations of patient plasma is determined against a curve made from a reference plasma provided.
Here's an analysis of the provided text regarding the REAADS von Willebrand Factor Antigen Test Kit, extracting the requested information:
Acceptance Criteria and Study Details for REAADS von Willebrand Factor Antigen Test Kit
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (Implied) | Reported Device Performance |
|---|---|
| Substantial Equivalence: | |
| Coefficient of Correlation | 0.962 |
| P-value (Single factor ANOVA) | 0.739 |
Note: The document states that the REAADS vWF:Ag Test Kit is compared to a legally marketed predicate device (Helena Von Willebrand Factor Antigen Rocket EIA) and a substantial equivalence claim is made. The acceptance criteria are implied by the statistical results presented to demonstrate this equivalence. Specifically, a high coefficient of correlation and a non-significant P-value (>.05) typically demonstrate statistical similarity and thus medical equivalence.
2. Sample Size for the Test Set and Data Provenance
The document refers to "Test results for clinical samples" but does not specify the exact sample size used for the test set.
The data provenance is also not explicitly stated in terms of country of origin or whether it was retrospective or prospective. It only mentions "clinical samples."
3. Number of Experts and their Qualifications for Ground Truth
The document does not mention the use of experts to establish ground truth for the test set. The comparison is made against a predicate device.
4. Adjudication Method for the Test Set
Not applicable/Not mentioned. Since a comparison was made against a predicate device's results directly, and not against an expert-adjudicated ground truth, no adjudication method is described.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No MRMC comparative effectiveness study was mentioned. This device is an in-vitro diagnostic test, not typically evaluated with MRMC studies involving human readers and AI assistance.
6. Standalone Performance Study
A standalone performance study was implicitly done by comparing the REAADS vWF:Ag Test Kit to the predicate device. The comparison directly evaluates the algorithm's (test kit's) performance against another established method.
7. Type of Ground Truth Used
The ground truth for the test set was essentially the results obtained from the legally marketed predicate device, the Helena Von Willebrand Factor Antigen Rocket EIA.
8. Sample Size for the Training Set
Not applicable/Not mentioned. This is a traditional ELISA-based test kit and does not involve AI or machine learning models that typically have "training sets." The development of such kits involves assay optimization and validation, not model training.
9. How the Ground Truth for the Training Set was Established
Not applicable/Not mentioned. As this is not an AI/ML device, the concept of a "training set" and establishing ground truth for it does not apply. The development would involve analytical validation and calibration using known concentrations of vWF:Ag.
§ 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).