(23 days)
The new Liquichek™ ANA Control, Centromere Pattern, Positive, is intended for use as an unassayed quality control to monitor indirect immunofluorescent testing of antinuclear antibodies (ANA).
This product is prepared from human serum with added preservatives. The control is provided in liquid form for convenience.
This document describes the Liquichek™ ANA Control, Centromere Pattern, Positive, a quality control device, and its acceptance criteria as demonstrated for substantial equivalence to a predicate device.
Here's a breakdown of the requested information:
1. A table of acceptance criteria and the reported device performance
For a quality control material like this, the "acceptance criteria" and "performance" are primarily related to its stability and its ability to consistently produce the intended "positive" result for Centromere pattern ANAs, which makes it suitable for monitoring tests.
| Acceptance Criteria | Reported Device Performance |
|---|---|
| Opened Vial Stability (Desired) | Analyte stable for 60 days when stored tightly capped at 2 to 8°C. |
| Shelf Life (Unopened Vial Stability) | Stable for 2 years when stored unopened at 2 to 8°C. |
| Matrix | Human Serum |
| Form | Liquid |
| Analyte | ANA Centromere Pattern |
| Intended Use | Unassayed quality control for monitoring indirect immunofluorescent testing of antinuclear antibodies (ANA). |
2. Sample sized used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
The document states, "Stability studies have been performed to determine the open vial stability and shelf life for the Liquichek™ ANA Control Centromere Pattern, Positive." and "Real time studies will be ongoing to support the shelf life of this product."
- Sample Size: The exact sample size (number of vials, replicates, etc.) used for these stability studies is not explicitly stated in the provided text.
- Data Provenance: The studies were conducted by Bio-Rad Laboratories, presumably at their facilities. The document doesn't specify if the data is retrospective or prospective, but as it refers to "ongoing" real-time studies, it implies a prospective data collection approach for shelf life confirmation. The country of origin would be the USA, where Bio-Rad Laboratories is based.
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)
Given that this is a quality control material intended for use in an indirect immunofluorescent assay (IFA) for antinuclear antibodies (ANA), the "ground truth" for the device itself would be its characterized performance and stability, rather than interpretations by experts in a diagnostic sense. The document does not mention the use of external experts for establishing the ground truth of the control's characteristics. The internal Bio-Rad scientists and quality control personnel would have characterized the material's properties.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
This type of adjudication method (e.g., 2+1, 3+1) is typically used in studies where human readers interpret medical images or complex diagnostic results, and their interpretations are compared to reach a consensus for ground truth. For a quality control material stability study, it is not applicable and therefore, no such method was employed or described. The performance is assessed through analytical testing results.
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
An MRMC comparative effectiveness study is relevant for diagnostic devices that involve significant human interpretation, especially when evaluating the impact of AI assistance. This device is a quality control material, not an AI-assisted diagnostic tool. Therefore, no MRMC study was performed or is relevant in this context, and there is no mention of AI assistance.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
This refers to the performance of an algorithm without human involvement. Since this device is a quality control material and not an algorithm or AI system, no standalone algorithm performance study was done or is applicable.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
For this quality control material, the "ground truth" for its performance is established through analytical characterization and stability testing against predefined specifications. This includes:
- Demonstrating the presence and appropriate titer of ANA Centromere pattern using established IFA methodologies.
- Measuring its stability over time under specified storage conditions through quantitative and qualitative analytical methods (e.g., retesting activity at various time points).
- Ensuring the matrix (human serum) and preservatives are appropriate and do not interfere with the intended use.
It is based on internal laboratory testing and compliance with quality control standards, rather than external expert consensus, pathology, or outcomes data in the clinical sense.
8. The sample size for the training set
This device is not an AI/machine learning model, so there is no "training set" in the conventional sense. The "training" or characterization of the control material is part of its manufacturing and quality assurance process, which involves preparing batches of the control and testing them to ensure they meet specifications.
9. How the ground truth for the training set was established
As there is no training set for an AI model, this question is not applicable. The "ground truth" for the control material itself is established through rigorous analytical testing and established manufacturing protocols to ensure it consistently provides the expected Centromere pattern ANA positive signal and maintains stability.
§ 866.5100 Antinuclear antibody immunological test system.
(a)
Identification. An antinuclear antibody immunological test system is a device that consists of the reagents used to measure by immunochemical techniques the autoimmune antibodies in serum, other body fluids, and tissues that react with cellular nuclear constituents (molecules present in the nucleus of a cell, such as ribonucleic acid, deoxyribonucleic acid, or nuclear proteins). The measurements aid in the diagnosis of systemic lupus erythematosus (a multisystem autoimmune disease in which antibodies attack the victim's own tissues), hepatitis (a liver disease), rheumatoid arthritis, Sjögren's syndrome (arthritis with inflammation of the eye, eyelid, and salivary glands), and systemic sclerosis (chronic hardening and shrinking of many body tissues).(b)
Classification. Class II (performance standards).