(59 days)
This in vitro diagnostic procedure is intended to quantitatively measure RF in human serum on the Cobas Mira chemistry analyzer. Such measurements are used in the diagnosis and treatment of rheumatoid arthritis.
The RF-LATEX "SEIKEN" is a reagent system for the quantitation of the concentration of rheumatoid factor (RF) in human serum. It is based on the agglutination of RF in serum with latex particles coated with anti-RF (human IgG). It employs the absorbance change observed as the basis for quantitation and calculates the amount of RF by interpolation from a calibration curve prepared from calibrators of known concentration. It is intended for use with the Cobas Mira chemistry analyzer (or other suitable analyzer).
Here's an analysis of the provided information regarding the acceptance criteria and study for the RF-LATEX "SEIKEN" device:
Acceptance Criteria and Device Performance
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria are implied by the comparison to the predicate device, "quantex RF plus," and the general performance expectations for in vitro diagnostic assays. The reported device performance for "RF-LATEX 'SEIKEN'" is directly provided.
| Performance Metric | Acceptance Criteria (Implied / Comparator) | RF-LATEX "SEIKEN" Reported Performance | Meets Criteria? |
|---|---|---|---|
| Minimum Detectable Conc. | 5 IU/ml (quantex RF plus) | 3 IU/ml | Yes (Better) |
| Precision (Between-run - CV%) | Less than 10% (quantex RF plus) | Sample 1: 1.59% | |
| Sample 2: 1.41% | |||
| Sample 3: 1.62% | Yes | ||
| Linearity Range | 5 - 100 IU/ml (quantex RF plus) | 3 - 120 IU/ml | Yes (Broader) |
| Correlation (r) | Not explicitly stated, but high correlation with predicate expected | 0.984 (vs quantex RF plus) | Yes (Excellent) |
| Within-run Precision (CV%) | Not explicitly stated, but typically low CV% expected | Sample 1: 2.95% | |
| Sample 2: 0.91% | |||
| Sample 3: 1.11% | |||
| Sample 4: 1.41% | |||
| Sample 5: 1.43% | Yes (Low CV%) | ||
| Reagent Stability (4°C) | Not explicitly stated, but consistent results over shelf life expected | Data provided for 15 months, showing consistent values for two lots across three samples. | Yes |
2. Sample Size for the Test Set and Data Provenance
- Sample Size for Accuracy/Correlation (Test Set): 92 serum samples.
- Data Provenance: The origin of the 92 serum samples is not explicitly stated beyond being "obtained." The data was "prepared at and which is on file at Denka Seiken, Co. Inc." It is a retrospective study as samples were "obtained" and tested. The country of origin for the data generation is implied to be Japan, given "Denka Seiken, Co. Inc."
3. Number of Experts Used to Establish Ground Truth for the Test Set and Their Qualifications
- Not applicable/provided. For this type of in vitro diagnostic device, the "ground truth" for each sample is the actual RF concentration as measured by a reference method or the comparative device, not an expert panel's interpretation.
4. Adjudication Method for the Test Set
- Not applicable. This is not an imaging or diagnostic interpretation task requiring adjudication of expert opinions. The comparison is quantitative based on assay measurements.
5. Multi Reader Multi Case (MRMC) Comparative Effectiveness Study
- No, a Multi Reader Multi Case (MRMC) comparative effectiveness study was not done. This study focuses on the performance of an in vitro diagnostic reagent system, not on human reader performance with or without AI assistance.
6. Standalone (Algorithm Only Without Human-in-the-Loop) Performance
- Yes, this study is a standalone performance evaluation of the RF-LATEX "SEIKEN" reagent system. The device operates as a laboratory assay, providing a quantitative result without direct human interpretation in its primary function. There is no human-in-the-loop component for the device's measurement process itself.
7. The Type of Ground Truth Used
- The ground truth for the accuracy/correlation study was established by comparing the measurements of the RF-LATEX "SEIKEN" device against those obtained from another commercially available, FDA-cleared device (quantex RF plus), which serves as a reference or predicate method. For precision, linearity, and stability, the ground truth is based on the known concentrations of quality control materials and calibrators, and the expected performance characteristics of a well-functioning assay.
8. The Sample Size for the Training Set
- Not applicable. This is a chemical reagent system, not a machine learning algorithm that requires a "training set" in the conventional sense. The development of such assays involves formulation, optimization, and characterization experiments, but 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 mentioned in the context of an algorithm. The development of the reagent system itself (e.g., optimizing reagent concentrations, reaction conditions) would have involved extensive R&D, likely using characterized samples and analytical methods to achieve desired performance, but this is not characterized as "ground truth for a training set."
§ 866.5775 Rheumatoid factor immunological test system.
(a)
Identification. A rheumatoid factor immunological test system is a device that consists of the reagents used to measure by immunochemical techniques the rheumatoid factor (antibodies to immunoglobulins) in serum, other body fluids, and tissues. Measurement of rheumatoid factor may aid in the diagnosis of rheumatoid arthritis.(b)
Classification. Class II (performance standards).