(136 days)
For the in vitro quantitative determination of free triiodothyronine (FT3) in human serum and plasma.
The Enzymun FT3 employs a competitive test principle with polyclonal antibodies directed against T3 and with streptavidin tubes.
• 1st Incubation: Sample (100 microliter) and a specific anti-T3 antibody are added to the streptavidin tube and all the FT3 present in the sample binds to the anti-T3 antibody-POD conjugate.
• 2nd Incubation: Incubation buffer (biotinylated T# polyhaptens) is added and binds with excess anti-T3 antibody-POD conjugate to the wall of the streptavidin tube.
• In the separation step, serum or plasma FT3-anti-T3 antibody-POD conjugate, excess biotinylated T3 polyhaptens and serum constituents are removed.
• The activity of the POD bound to the tube wall is determined photometrically after the addition of the chromogen and the substrate H2O2 (from sodium perborate). In the indicator reaction, the chromophore formed is a dark green cation whose concentration is indirectly proportional to the FT3 concentration in the sample. Results are determined via a calibration curve.
The provided 510(k) summary for the Enzymun-Test® FT3 focuses on establishing substantial equivalence to the predicate device (Diagnostic Products Corp. FT3) for the quantitative determination of free triiodothyronine (FT3) in human serum and plasma. The acceptance criteria and performance data provided relate to the device's analytical performance, not clinical efficacy in the context of human-in-the-loop or MRMC studies.
Here's a breakdown of the requested information based on the provided text:
1. A table of acceptance criteria and the reported device performance
The document does not explicitly state "acceptance criteria" with numerical targets for each performance metric, but rather presents a comparison. However, the reported performance metrics for the Enzymun FT3 are:
| Metric | Acceptance Criteria (Implied) | Reported Device Performance (Enzymun FT3) |
|---|---|---|
| Intended use | Immunoassay for in vitro quantitative determination of FT3 | Immunoassay for in vitro quantitative determination of free triiodothyronine (FT3) in human serum and plasma |
| Test Principle | Competitive test principle | Competitive test principle with polyclonal antibodies against T3 and streptavidin tubes |
| Sample Type & Volume | Serum and plasma, 100μl | Serum and plasma, 100μl |
| Standardization | Weighed in standards | Weighed in standards |
| Reaction Test Principle | N/A (compared to predicate) | streptavidin microparticles and electrochemiluminescence technology |
| Instrument Required | N/A (compared to predicate) | ES 300 |
| Measuring Range | N/A (compared to predicate) | 0.5 to 30 pg/mL |
The direct numeric comparator for "acceptance" is the performance of the predicate device. For example, the measuring range of the Enzymun FT3 (0.5 to 30 pg/mL) is considered acceptable because it overlaps significantly with the predicate DPC FT3 (0.5 to 42 pg/mL). The core assertion is substantial equivalence, not necessarily superiority across all metrics.
2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
The provided text does not contain information regarding the sample size used for any test set or the data provenance (country of origin, retrospective/prospective). This document primarily details the general characteristics and intended use of the device, along with a high-level comparison to a predicate device.
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)
This information is not applicable and not provided in the document. The device is an in vitro diagnostic (IVD) for quantitative measurement of a biomarker (FT3). Ground truth in this context typically refers to analytical accuracy and precision established through reference methods and certified calibrators, not expert interpretation of images or clinical cases.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
This information is not applicable and not provided in the document. Adjudication methods like 2+1 or 3+1 are relevant for studies involving human interpretation or clinical endpoints, where disagreement among experts needs resolution. For an IVD, analytical performance is assessed against established reference methods or internal standards.
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 was not done. This type of study is relevant for medical imaging devices or AI-assisted diagnostic tools where human readers interpret data. The Enzymun-Test® FT3 is an in vitro diagnostic assay, meaning it directly measures a chemical concentration in a sample, and does not involve human readers interpreting complex images or data in the same way.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
The device itself is a standalone diagnostic test in the sense that it performs the measurement algorithmically via its reagents and instrument (ES 300). The output is a quantitative FT3 concentration. The comparison to the predicate device and the description of the reaction principle constitute the "standalone performance" characterization for such an IVD. There is no explicit mention of "an algorithm" separate from the chemical assay in the context of AI.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
The "ground truth" for an IVD like the Enzymun-Test® FT3 would typically be established through:
- Reference methods: Highly accurate and precise laboratory methods (e.g., mass spectrometry) for measuring FT3.
- Certified reference materials/calibrators: Samples with known, validated concentrations of FT3 used to calibrate the assay and verify accuracy.
- Method comparison studies: Comparing the results of the new device against an established, legally marketed device (the predicate).
While not explicitly stated as "ground truth," the comparison to the DPC FT3 predicate implies that the predicate's performance serves as a benchmark for acceptability.
8. The sample size for the training set
This information is not applicable and not provided. The Enzymun-Test® FT3 is a traditional immunoassay, not a machine learning or AI-driven device that requires training sets in the computational sense. Its development involves chemical and biological optimization, calibration, and validation rather than algorithmic training.
9. How the ground truth for the training set was established
This information is not applicable as there is no "training set" in the context of a machine learning algorithm. The "ground truth" for calibrating and validating the immunoassay's performance would have been established through methods described in point 7 during the device's analytical development.
§ 862.1710 Total triiodothyronine test system.
(a)
Identification. A total triiodothyronine test system is a device intended to measure the hormone triiodothyronine in serum and plasma. Measurements obtained by this device are used in the diagnosis and treatment of thyroid diseases such as hyperthyroidism.(b)
Classification. Class II. This device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 862.9.