(23 days)
The Liquichek™ ANA Control, Nucleolar 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.
Here's a breakdown of the acceptance criteria and study information for the Liquichek™ ANA Control Nucleolar Pattern, Positive device, based on the provided text:
Acceptance Criteria and Device Performance
This submission focuses on establishing the stability claims for a quality control material. Therefore, the "acceptance criteria" are the stability periods claimed by the manufacturer, and the "reported device performance" is the confirmation that these stability periods were met in the studies.
| Acceptance Criteria (Target) | Reported Device Performance (Achieved) |
|---|---|
| Opened Vial Stability: Stable for 60 days when stored tightly capped at 2 to 8°C. | The analyte is stable for 60 days when the control is opened and stored tightly capped at 2 to 8°C. |
| Shelf Life (Unopened): Stable for 2 years when stored unopened at 2 to 8°C. | The control is stable for 2 years when stored unopened at 2 to 8°C. |
Note: The document explicitly states that "Real time studies will be ongoing to support the shelf life of this product," indicating that the 2-year shelf life claim might be based on accelerated stability studies or early real-time data, with full real-time data still being collected.
Study Details
Based on the provided text, the study focuses on product stability. Information regarding analytical performance (e.g., sensitivity, specificity, accuracy) would typically be relevant for diagnostic devices that are intended to measure an analyte. As this is a quality control device, the primary "performance" is its stability and ability to maintain its characteristics over time.
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Sample Size Used for the Test Set and Data Provenance:
- Sample Size: Not explicitly stated in terms of number of vials or batches tested. The study involves assessing the control material's stability over time.
- Data Provenance: Not explicitly stated, but assumed to be internal laboratory studies conducted by Bio-Rad Laboratories in the USA, where the submitter is located. The studies are described as "stability studies." They are likely prospective in nature, as they involve monitoring the product over time to define stability claims.
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Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications:
- Not applicable. For a quality control material's stability study, "ground truth" is typically established by objective measurements of the analyte's presence and pattern (in this case, ANA Nucleolar Pattern) at various time points, compared to initial measurements. This doesn't involve human expert interpretation in the same way a diagnostic imaging study would. The analysis would be performed by trained laboratory personnel following established protocols.
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Adjudication Method for the Test Set:
- Not applicable. Adjudication methods like "2+1" are relevant for resolving discrepancies in human expert interpretations (e.g., in an imaging study). For a stability study, the performance is measured objectively, and statistical methods (e.g., comparing measurements to acceptance limits) would be used to determine if the product remains stable.
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Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:
- No, a MRMC comparative effectiveness study was not done. This type of study is relevant for evaluating the impact of an AI system on human reader performance, typically in diagnostic interpretation tasks. The Liquichek™ ANA Control is a quality control material, not a diagnostic AI system.
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Standalone Performance Study:
- Yes, a standalone study was essentially performed. The stability studies evaluate the performance of the control material (its ability to maintain the ANA Nucleolar Pattern) independently, over time, without human intervention as a variable in the stability assessment itself. The "algorithm" here is the inherent chemical and biological stability of the control material.
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Type of Ground Truth Used:
- The "ground truth" for the stability study is the inherent characteristic of the control (presence of ANA Nucleolar Pattern reactivity) as measured at baseline and validated against established laboratory standards for ANA testing. Over time, subsequent measurements are compared against this initial "truth" to ensure the pattern and reactivity are maintained within acceptable limits. This would involve specific laboratory assays (indirect immunofluorescence) and objective assessment of the fluorescence pattern.
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Sample Size for the Training Set:
- Not applicable. This device is a quality control material, not an AI or machine learning model that requires a "training set."
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How the Ground Truth for the Training Set Was Established:
- Not applicable, as explained above.
§ 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).