(147 days)
In vitro diagnostic reagents for the quantitative determination of a -antitrypsin in human serum, heparinized and EDTA plasma by means of immunonephelometery on the BN™ Systems. The measurement of a-antitrypsin aids in the diagnosis of several conditions including adult cirrhosis of the liver. In addition, a r-antitrypsin deficiency has been associated with pulmonary emphysema in conjunction with other laboratory and clinical findings.
Proteins contained in human body fluids form immune complexes in an immunochemical reaction with specific antibodies. These complexes statter a beam of light passed through the sample. The intensity of the scattered light is proportional to the concentration of the relevant protein in the sample. The result is evaluated by comparison with a standard of known concentration.
This document describes the N Antisera to Human α-Antitrypsin Assay, an in vitro diagnostic reagent for the quantitative determination of alpha-1-antitrypsin (α1-AT) in human serum, heparinized, and EDTA plasma using immunonephelometry on the BN™ Systems.
1. Acceptance Criteria and Reported Device Performance:
The document does not explicitly state pre-defined acceptance criteria in terms of numerical thresholds for a specific performance metric. Instead, the "device performance characteristics" section in the K053072 summary focuses on demonstrating equivalence in measurement between different sample types (serum, heparinized plasma, and EDTA plasma) and to a legally marketed predicate device.
The reported device performance is based on method comparison studies:
| Acceptance Criteria (Implied) | Reported Device Performance |
|---|---|
| Equivalence in measurement between serum and heparinized or EDTA plasma. | Correlation coefficients between 0.97 and 0.99 for method comparisons. |
| Substantial equivalence to the predicate device (N Antisera to Human α-Antitrypsin, K860894). | The modified assay demonstrated equivalent performance to the predicate device for quantitative determination of α-antitrypsin by immunonephelometry on BN™ Systems. |
Study Proving Acceptance Criteria:
The study proving the device meets its implied acceptance criteria of equivalence was a method comparison study.
2. Sample Size Used for the Test Set and Data Provenance:
- Sample Size: The document does not specify the exact sample size for the test set used in the method comparison studies. It only states that "method comparisons were performed."
- Data Provenance: The document does not explicitly state the country of origin of the data or whether the study was retrospective or prospective. Given that the manufacturer is based in Germany (Dade Behring Marburg GmbH) and the contact information for regulatory submission is in the US (Dade Behring Inc.), the data could be from various global sites.
3. Number of Experts Used to Establish Ground Truth and Qualifications:
Not applicable. This device is an in vitro diagnostic reagent for quantitative measurement of a biomarker. The "ground truth" for method comparison studies would typically be the results obtained from a reference method or the established predicate device, not expert consensus on qualitative interpretation.
4. Adjudication Method:
Not applicable. As described above, this is a quantitative measurement, and adjudication by experts is not a relevant component of its validation.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:
Not applicable. An MRMC study is relevant for devices that involve human interpretation of images or other qualitative data, particularly in the context of diagnostic accuracy. This device is an automated quantitative reagent.
6. Standalone Performance Study:
Yes, a standalone performance study was conducted in the sense that the device's analytical performance (specifically, its ability to yield comparable quantitative results across different sample matrices) was evaluated intrinsically. The method comparison studies demonstrated the performance of the algorithm/reagent by itself in generating the quantitative alpha-1-antitrypsin values. This means the analytical performance of the device without human interpretation was assessed.
7. Type of Ground Truth Used:
The "ground truth" for the method comparison studies would be the quantitative results obtained from:
- Measurements using the predicate device (N Antisera to Human α-Antitrypsin, K860894), for establishing substantial equivalence.
- Measurements from serum samples when comparing performance with heparinized and EDTA plasma. This implies that serum is considered the primary, well-established matrix for α1-AT determination against which other matrices are compared.
8. Sample Size for the Training Set:
Not applicable. This device is a reagent for an immunonephelometry system. It is not an AI/ML algorithm that requires a "training set" in the conventional sense of machine learning. The "training" of such a system would involve calibration curves and reagent optimization, which are part of the manufacturing and method development process, not a distinct training set for an algorithm.
9. How the Ground Truth for the Training Set Was Established:
Not applicable, as there is no "training set" in the context of an AI/ML algorithm. The calibration and optimization of the reagent and system would follow established laboratory practices for IVD assays, using certified reference materials or well-characterized control sera with known α1-AT concentrations to establish calibration curves. This is an analytical validation process, not a ground truth establishment for a training set.
§ 866.5130
Alpha -1-antitrypsin immunological test system.(a)
Identification. Analpha -1-antitrypsin immunological test system is a device that consists of the reagents used to measure by immunochemical techniques thealpha -1-antitrypsin (a plasma protein) in serum, other body fluids, and tissues. The measurements aid in the diagnosis of several conditions including juvenile and adult cirrhosis of the liver. In addition,alpha -1-antitrypsin deficiency has been associated with pulmonary emphysema.(b)
Classification. Class II (performance standards).