(65 days)
The Access Testosterone assay is a paramagnetic particle, chemiluminescent immunoassay for the quantitative determination of total testosterone levels in human serum and plasma using the Access Immunoassay Systems.
Measurement of testosterone are used in the diagnosis and treatment of disorders involving the male sex hormones (androgens), including primary and secondary hypogonadism, delayed or precocious puberty, impotence in males and, in females hirsutism (excessive hair) and virilization) due to tumors, polycystic ovaries, and adrenogenital syndromes.
The Access Testosterone assay is a competitive binding immunoenzymatic assay. The Access Testosterone assay consists of the reagent pack and calibrators. Other items needed to run the assay include substrate and wash buffer. The Access Testosterone assay reagent pack, Access Testosterone assay calibrators, along with the UniCel Dxl wash buffer II are designed for use with the Dxl 9000 Access Immunoassay Analyzer in a clinical laboratory setting.
The provided text describes the analytical performance verification of an in vitro diagnostic device (Access Testosterone Assay) and its substantial equivalence to a previously cleared device, rather than an AI-powered medical device performing image analysis or similar tasks that typically involve human experts for ground truth and MRMC studies.
Therefore, many of the requested elements for an AI device (like human expert adjudication, MRMC studies, effect size of human improvement with AI, or detailed ground truth establishment for a training set) are not applicable to this document.
However, I can extract the relevant information regarding the acceptance criteria and study that proves the device meets them for this in vitro diagnostic device.
Here's the information based on the provided text:
Acceptance Criteria and Device Performance for Access Testosterone Assay
1. Table of Acceptance Criteria and Reported Device Performance
| Test | Acceptance Criteria | Reported Device Performance |
|---|---|---|
| Method Comparison | R² ≥ 0.90 and Slope of 1.00 ± 0.14 | R² = 0.98, Slope = 0.95 (95% CI: 0.93, 0.98), Intercept = 0.028 (95% CI: -0.015, 0.071) |
| Linearity (Analytical Measuring Interval) | Linear throughout the analytical measuring interval of 0.4 - 16.0 ng/mL | Linear throughout the analytical measuring interval of 0.4 - 16.0 ng/mL |
| Imprecision (Within-Laboratory) | ≤ 0.14 ng/mL SD at concentrations ≤ 1.4 ng/mL | Sample 1 (0.71 ng/mL): SD = 0.04 (meets criteria) |
| ≤ 10.0% CV at concentrations > 1.4 ng/mL | Sample 2 (2.0 ng/mL): CV = 4.4% (meets criteria) | |
| Sample 3 (4.8 ng/mL): CV = 3.9% (meets criteria) | ||
| Sample 4 (7.1 ng/mL): CV = 4.6% (meets criteria) | ||
| Sample 5 (8.6 ng/mL): CV = 5.9% (meets criteria) | ||
| Sample 6 (14 ng/mL): CV = 7.8% (meets criteria) | ||
| Limit of Blank (LoB) | Not explicitly stated as a numerical acceptance criterion, but determined and accepted. | LoB = 0.2 ng/mL |
| Limit of Detection (LoD) | Not explicitly stated as a numerical acceptance criterion, but determined and accepted. | LoD = 0.4 ng/mL |
| Limit of Quantitation (LoQ) | Not explicitly stated as a numerical acceptance criterion, but determined and accepted. | 20% Within-Laboratory CV LoQ = 0.4 ng/mL |
2. Sample Size Used for the Test Set and Data Provenance
- Method Comparison: 108 serum samples.
- Linearity: Low sample (native serum), high sample (native serum spiked with Testosterone antigen), and mixtures of low and high samples. (Specific N not further detailed for mixtures, but implies multiple points across measuring interval).
- Imprecision: Six (6) serum samples (2 native, 3 pooled native, 1 spiked native). Each tested in replicates of two (2) per run, with two (2) runs per day for a minimum of 20 days on each instrument and reagent lot combination. (N=88 for each sample shown in table corresponds to total replicates across the study design).
- LoB: Four blank samples.
- LoD: Seven serum samples containing low levels of Testosterone.
- LoQ: Twelve serum samples containing low levels of Testosterone.
- Data Provenance: Not explicitly stated (e.g., country of origin, retrospective/prospective). However, given it's an IVD, samples would be collected for analytical performance testing.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications of Experts
- Not applicable (N/A). This device is an in vitro diagnostic assay for quantitative determination of a hormone level. Ground truth (or reference values) for analytical performance are established through established analytical methods, reference materials (e.g., USP Reference Material for Standardization and Traceability), and quantitative measurement procedures, not by human expert opinion or interpretation of images.
4. Adjudication Method for the Test Set
- N/A. Adjudication by human experts is not relevant for establishing the analytical performance of an in vitro diagnostic assay.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done, and its effect size of human readers improve with AI vs. without AI assistance
- N/A. This is not an AI-powered device involving human readers or interpretation. It's an in vitro diagnostic assay.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done
- Yes, in essence. The studies described (Method Comparison, Linearity, Imprecision, LoB/LoD/LoQ) demonstrate the analytical performance of the device itself (the Access Testosterone Assay on the Dxl 9000 Access Immunoassay Analyzer) in a standalone, automated manner. There is no human interpretation component where performance needs to be evaluated.
7. The Type of Ground Truth Used
- Analytical Ground Truth:
- Reference Method/Predicate Device: For method comparison, the "previously cleared system" (Access Testosterone assay on the Access 2 instrument) serves as the reference for comparison, indicating that its results are considered the comparative "ground truth."
- Known Concentrations/Standards/Reference Materials: For linearity, imprecision, and limit studies, samples with known or characterized concentrations (e.g., native serum, spiked samples, blank samples) and established reference materials (USP Reference Material) are used.
- Statistical Models/Calculations: LoB, LoD, and LoQ are determined statistically based on measurements of blank and low-level samples, following CLSI guidelines.
8. The Sample Size for the Training Set
- N/A. This is an in vitro diagnostic device, not an AI/machine learning model that undergoes a "training" phase with a data set in the conventional sense. The "training" in manufacturing involves calibrating the instrument and reagents according to established protocols, not learning from a dataset.
9. How the Ground Truth for the Training Set was Established
- N/A. As above, there is no "training set" in the context of an AI model for this device. Calibration and quality control procedures ensure the analytical performance by using calibrators and controls with known values, which are traceable to reference materials (e.g., USP Reference Material).
§ 862.1680 Testosterone test system.
(a)
Identification. A testosterone test system is a device intended to measure testosterone (a male sex hormone) in serum, plasma, and urine. Measurement of testosterone are used in the diagnosis and treatment of disorders involving the male sex hormones (androgens), including primary and secondary hypogonadism, delayed or precocious puberty, impotence in males and, in females hirsutism (excessive hair) and virilization (masculinization) due to tumors, polycystic ovaries, and adrenogenital syndromes.(b)
Classification. Class I.