(64 days)
The VisuLize™ Factor IX Antigen Kit is intended for use as an in vitro diagnostic assay for the quantitative determination of Factor IX antigen in human plasma samples and Factor IX concentrates using the double antibody enzyme linked immuno-sorbent assay (ELISA).
The VisuLize™ Factor IX Antigen kit is a sandwich enzyme-linked immuno-sorbent assay (ELISA) using a polyclonal antibody coated 96-microwell format. Plasma samples are diluted and applied to the pre-coated wells. After washing away unbound proteins, a horseradish peroxidase (HRP) labelled polyclonal antibody is applied to detect the captured Factor IX. A chromogenic substrate (TMB containing H2O2) is added to allow for color development. The color formed is measured spectrophotometrically at 450 nm, with the absorbance being directly proportional to the concentration of Factor IX that was in the sample.
Here's the breakdown of the acceptance criteria and the study details for the VisuLize Factor IX Antigen Kit, based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance:
| Acceptance Criteria (Implied) | Reported Device Performance (VisuLize™ Factor IX Antigen Kit) | Predicate Device Performance (Asserachrom IX:AG Kit) |
|---|---|---|
| Intra-Assay Precision (CV%) | 3.24% - 8.78% | 5.31% - 5.84% |
| Inter-Assay Precision (CV%) | 2.96% - 6.84% | 5.99% - 6.39% |
| Linearity | Log-log curve, R² ≥ 0.990 | Log-log graph (no specific R² mentioned) |
| Detection Limit | 0.005 IU/mL (equivalent to 0.5%) | 1% |
| Clinical Correlation (r) | Internal Testing: 0.987 | Not applicable (this is a comparison metric) |
| P-value (ANOVA) | Internal Testing: 0.528 | Not applicable (this is a comparison metric) |
| Clinical Correlation (r) | External Testing Site #1: 0.976 | Not applicable (this is a comparison metric) |
| P-value (ANOVA) | External Testing Site #1: 0.458 | Not applicable (this is a comparison metric) |
| Clinical Correlation (r) | External Testing Site #2: 0.982 | Not applicable (this is a comparison metric) |
| P-value (ANOVA) | External Testing Site #2: 0.228 | Not applicable (this is a comparison metric) |
Note: The document does not explicitly state numerical acceptance criteria for the VisuLize kit. Instead, it demonstrates "substantial equivalence" to the predicate device by showing comparable or better performance for analytical metrics (precision, linearity, detection limit) and excellent correlation in clinical studies. The "acceptance criteria" are therefore inferred from the comparison to the predicate device, implying that performance similar to or better than the predicate is acceptable.
2. Sample Sizes Used for the Test Set and Data Provenance:
- Internal Testing: 134 samples
- External Testing Site #1: 114 samples
- External Testing Site #2: 109 samples
- Total Test Set Sample Size: 357 samples (134 + 114 + 109)
- Data Provenance: The document states "Testing of clinical samples across the clinical range was conducted internally and by two external testing sites." It doesn't explicitly state the country of origin for the samples or whether they were retrospective or prospective, but the company is based in Ancaster, ON, Canada, hinting at Canadian origin for internal testing. The external sites are not specified geographically. Given this is a 510(k) summary, it's highly likely these were retrospective samples from stored banks, or an observational study, rather than a prospective clinical trial, focused on method comparison.
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. For an immunoassay like this, the "ground truth" for the clinical performance comparison is the result obtained from the predicate device (Asserachrom IX:AG Kit). The study compares the results of the proposed device to the predicate device, assuming the predicate device provides the established "truth" for Factor IX antigen levels. It doesn't involve expert consensus on the diagnosis of a condition but rather the measurement of an analyte.
4. Adjudication Method for the Test Set:
This information is not applicable and not provided. Adjudication typically refers to resolving discrepancies between multiple readers or diagnostic methods for qualitative assessments (e.g., presence/absence of a disease). In this quantitative assay, the comparison is made between two analytical methods, and statistical measures like Pearson correlation and ANOVA are used to assess agreement, not adjudication.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done, and the Effect Size:
No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not done. This type of study focuses on human readers' performance with and without AI assistance, which is not relevant for a standalone in-vitro diagnostic (IVD) kit that quantitatively measures an analyte. The study conducted was a method comparison study between a new IVD kit and a legally marketed predicate IVD kit.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done:
Yes, a standalone performance study was done. The VisuLize™ Factor IX Antigen Kit is an in-vitro diagnostic assay. Its performance (precision, linearity, detection limit, and correlation with the predicate) was evaluated based on the kit's direct output, without human interpretation or intervention in the measurement itself. The human involvement is limited to performing the assay according to instructions and interpreting the quantitative result.
7. The Type of Ground Truth Used:
The "ground truth" for the clinical performance comparison was the quantitative Factor IX Antigen measurements obtained from the predicate device, the Asserachrom IX:AG Kit. The study aimed to show that the new device produced results consistent with an already legally marketed and accepted device.
8. The Sample Size for the Training Set:
The document does not provide information about a specific "training set" or its sample size. For an ELISA kit, "training" is more about optimizing the assay components and protocol during development rather than training a machine learning model on a distinct dataset. The presented data are for validation/testing of the finalized kit's performance against the predicate.
9. How the Ground Truth for the Training Set Was Established:
As there is no explicit mention of a "training set" in the context of machine learning, this question is not applicable. The development of the assay would have involved standard laboratory practices for optimizing reagent concentrations, incubation times, wash steps, etc. The "ground truth" during this development phase would have been established through internal validation experiments, likely using reference materials and potentially comparing early versions of the assay to existing methods, but this is not explicitly detailed as a formal "training set" with established ground truth in the context of this 510(k) submission.
§ 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).